Yubico, Inc.
YubiKey 5 Cryptographic Module
FIPS 140-3 Non-Proprietary Security Policy
Version 1.0
Non-Proprietary Security Policy for Yubico, Inc., YubiKey 5 Cryptographic Module
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TABLE OF CONTENTS
1 General .......................................................................................................................................................................6
1.1 Overview .............................................................................................................................................................6
1.2 Security Levels.....................................................................................................................................................6
2 Cryptographic Module Specification ..........................................................................................................................7
2.1 Description ..........................................................................................................................................................7
2.2 Tested and Vendor Affirmed Module Version and Identification.......................................................................8
2.3 Excluded Components.........................................................................................................................................9
2.4 Modes of Operation............................................................................................................................................9
2.5 Algorithms.........................................................................................................................................................10
2.6 Security Function Implementations ..................................................................................................................14
2.7 Algorithm Specific Information .........................................................................................................................19
2.8 RBG and Entropy ...............................................................................................................................................20
2.9 Key Generation..................................................................................................................................................20
2.10 Key Establishment...........................................................................................................................................20
2.11 Industry Protocols ...........................................................................................................................................20
3 Cryptographic Module Interfaces.............................................................................................................................21
3.1 Ports and Interfaces ..........................................................................................................................................21
4 Roles, Services, and Authentication .........................................................................................................................21
4.1 Authentication Methods ...................................................................................................................................21
4.2 Roles..................................................................................................................................................................23
4.3 Approved Services.............................................................................................................................................23
4.4 Non-Approved Services.....................................................................................................................................50
4.5 External Software/Firmware Loaded ................................................................................................................50
5 Software/Firmware Security.....................................................................................................................................51
5.1 Integrity Techniques..........................................................................................................................................51
5.2 Initiate on Demand............................................................................................................................................51
6 Operational Environment.........................................................................................................................................51
6.1 Operational Environment Type and Requirements ..........................................................................................51
7 Physical Security .......................................................................................................................................................51
7.1 Mechanisms and Actions Required...................................................................................................................51
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7.2 EFP/EFT Information .........................................................................................................................................51
7.3 Hardness Testing Temperature Ranges.............................................................................................................52
8 Non-Invasive Security ...............................................................................................................................................52
8.1 Mitigation Techniques.......................................................................................................................................52
9 Sensitive Security Parameters Management............................................................................................................52
9.1 Storage Areas ....................................................................................................................................................52
9.2 SSP Input-Output Methods ...............................................................................................................................53
9.3 SSP Zeroization Methods...................................................................................................................................53
9.4 SSPs ...................................................................................................................................................................55
10 Self-Tests.................................................................................................................................................................61
10.1 Pre-Operational Self-Tests ..............................................................................................................................61
10.2 Conditional Self-Tests......................................................................................................................................61
10.3 Periodic Self-Test Information.........................................................................................................................63
10.4 Error States......................................................................................................................................................64
10.5 Operator Initiation of Self-Tests......................................................................................................................65
11 Life-Cycle Assurance ...............................................................................................................................................65
11.1 Installation, Initialization, and Startup Procedures.........................................................................................65
11.2 Administrator Guidance..................................................................................................................................66
11.3 Non-Administrator Guidance..........................................................................................................................66
11.4 Design and Rules .............................................................................................................................................66
11.5 End of Life........................................................................................................................................................67
12 Mitigation of Other Attacks....................................................................................................................................67
13 References..............................................................................................................................................................67
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LIST OF TABLES
Table 1: Security Levels..................................................................................................................................................7
Table 2: Tested Module Identification – Hardware.......................................................................................................8
Table 3: Modes List and Description..............................................................................................................................9
Table 4: Approved Algorithms.....................................................................................................................................12
Table 5: Vendor-Affirmed Algorithms .........................................................................................................................13
Table 6: Non-Approved, Allowed Algorithms..............................................................................................................13
Table 7: Non-Approved, Allowed Algorithms with No Security Claimed.....................................................................13
Table 8: Non-Approved, Not Allowed Algorithms .......................................................................................................14
Table 9: Security Function Implementations...............................................................................................................19
Table 10: Entropy Certificates .....................................................................................................................................20
Table 11: Entropy Sources...........................................................................................................................................20
Table 12: Ports and Interfaces.....................................................................................................................................21
Table 13: Authentication Methods..............................................................................................................................22
Table 14: Roles.............................................................................................................................................................23
Table 15: Approved Services .......................................................................................................................................49
Table 16: Non-Approved Services................................................................................................................................50
Table 17: Mechanisms and Actions Required..............................................................................................................51
Table 18: EFP/EFT Information....................................................................................................................................52
Table 19: Hardness Testing Temperatures..................................................................................................................52
Table 20: Storage Areas...............................................................................................................................................53
Table 21: SSP Input-Output Methods..........................................................................................................................53
Table 22: SSP Zeroization Methods .............................................................................................................................54
Table 23: SSP Table 1...................................................................................................................................................57
Table 24: SSP Table 2...................................................................................................................................................60
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Table 25: Pre-Operational Self-Tests...........................................................................................................................61
Table 26: Conditional Self-Tests ..................................................................................................................................63
Table 27: Pre-Operational Periodic Information .........................................................................................................63
Table 28: Conditional Periodic Information.................................................................................................................64
Table 29: Error States ..................................................................................................................................................65
List of Figures
Figure 1: YubiKey 5 Cryptographic Module ...................................................................................................................7
Figure 2: Block Diagram.................................................................................................................................................8
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1 GENERAL
1.1 OVERVIEW
This document defines the Security Policy for the Yubico, Inc. (Yubico) YubiKey 5 Cryptographic Module, hereafter
“the module”.
The physical form of the module is depicted in Figure 1. The module is a single-chip embodiment as defined by FIPS
140-3 and conforms to Security Level 2.
1.2 SECURITY LEVELS
The module meets the overall requirements of FIPS 140-3 Security Level 2.
Section Title Security Level
1 General 2
2 Cryptographic module specification 2
3 Cryptographic module interfaces 2
4 Roles, services, and authentication 2
5 Software/Firmware security 2
6 Operational environment N/A
7 Physical security 3
8 Non-invasive security N/A
9 Sensitive security parameter management 2
10 Self-tests 2
11 Life-cycle assurance 2
12 Mitigation of other attacks N/A
Overall Level 2
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Table 1: Security Levels
2 CRYPTOGRAPHIC MODULE SPECIFICATION
2.1 DESCRIPTION
The YubiKey 5 Cryptographic Module (the module) is a single-chip module validated at FIPS 140-3 Security Level 2.
The module is a secure element that supports multiple protocols designed to be embedded in USB and/or NFC
security tokens. The module can generate, store, and perform cryptographic operations for sensitive data and can
be utilized via an external touch-button for Test of User Presence in addition to PIN for smartcard authentication.
The module implements several major functions - FIDO, PIV-compatible smartcard, OpenPGP smartcard, OATH
authentication, Security Domain, and YubiHSM Auth.
Figure 1: YubiKey 5 Cryptographic Module
Purpose and Use:
The YubiKey 5 Cryptographic Module is the core component for authenticators in the YubiKey 5 product family and
supports several functional units: FIDO, PIV, OpenPGP, OATH, Security Domain, and YubiHSM Auth.
Module Type: Hardware
Module Embodiment: SingleChip
Module Characteristics:
The critical components within the module are encapsulated inside a single, integrated circuit. Please note that
NFC is supported as a communication layer, but the antenna and wireless capability is outside of the module’s
boundary; as such, the wireless capability is not part of the validation.
Cryptographic Boundary:
The cryptographic boundary is defined as the IC package that comprises the Infineon Technologies SLE
78CLUFX5000P.
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Figure 2: Block Diagram
2.2 TESTED AND VENDOR AFFIRMED MODULE VERSION AND IDENTIFICATION
The YubiKey 5 Cryptographic Module is designed to meet the requirements of FIPS 140-3 Security Level 2 (refer to
Table 1). The module is available in the following configuration (refer to Table 2):
Tested Module Identification – Hardware:
Model and/or
Part Number
Hardware
Version
Firmware
Version
Processors Features
SLE78CLUFX5000P SLE78CLUFX5000P 5.7.4 SLE78CLUFX5000P Single-Chip
Table 2: Tested Module Identification – Hardware
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N.B. The module returns the hardware identifier ‘78CLUFX5000P’ and firmware version ‘5.7.4’ when queried.
Tested Module Identification – Software, Firmware, Hybrid (Executable Code Sets):
N/A for this module.
Tested Module Identification – Hybrid Disjoint Hardware:
N/A for this module.
Tested Operational Environments - Software, Firmware, Hybrid:
N/A for this module.
Vendor-Affirmed Operational Environments - Software, Firmware, Hybrid:
N/A for this module.
CMVP makes no statement as to the correct operation of the module or the security strengths of the generated
keys when so ported if the specific operational environment is not listed on the validation certificate.
2.3 EXCLUDED COMPONENTS
There are no components excluded from the cryptographic boundary.
2.4 MODES OF OPERATION
Modes List and Description:
The module supports an Approved mode and a non-Approved mode of operation. The Approved mode must be
initialized per the instructions in this Security Policy. The module does not support a degraded mode of operation
or a maintenance interface.
Mode Name Description Type Status Indicator
Approved All functional units other
than OTP
Approved The "Slot YK Get Device Info" service results in
an error.
Non-
Approved
OTP functional unit services Non-
Approved
The "Slot YK Get Device Info" service resolves
successfully.
Table 3: Modes List and Description
The module powers up in an uninitialized state upon first use. The operator must configure the module per the
instructions provided in Section 11.1. Once this process is completed, the module enters the Approved mode. The
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module retains its current configuration settings across power-cycling. The module is single-threaded: while one
service is in process, no other service is.
Mode Change Instructions and Status:
The module enters the non-Approved mode whenever a non-Approved service is invoked and exits when the said
service completes.
The only non-Approved services are contained by the OTP functional unit. In order to access the OTP functional
unit, OTP must be selected (NFC) or the designated OTP endpoints must be used (USB). While OTP is selected, no
other services beyond OTP services, namely those listed in Section 4.4, are available.
2.5 ALGORITHMS
The YubiKey 5 Cryptographic Module supports the approved cryptographic algorithms shown in Table 4.
Approved Algorithms:
The module supports the following approved cryptographic algorithms.
Algorithm CAVP Cert Properties Reference
AES-CBC A5891 Direction - Decrypt, Encrypt
Key Length - 128, 192, 256
SP 800-38A
AES-CCM A5891 Key Length - 128, 192, 256 SP 800-38C
AES-CMAC A5891 Direction - Generation, Verification
Key Length - 128, 192, 256
SP 800-38B
AES-ECB A5891 Direction - Decrypt, Encrypt
Key Length - 128, 192, 256
SP 800-38A
Counter DRBG A5891 Prediction Resistance - No
Mode - AES-256
Derivation Function Enabled - Yes
SP 800-90A
Rev. 1
ECDSA KeyGen (FIPS186-5) A5891 Curve - P-224, P-256, P-384, P-521
Secret Generation Mode - testing candidates
FIPS 186-5
ECDSA SigGen (FIPS186-5) A5891 Curve - P-224, P-256, P-384, P-521
Hash Algorithm - SHA2-256, SHA2-384, SHA2-
512
Component - Yes
FIPS 186-5
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Algorithm CAVP Cert Properties Reference
ECDSA SigVer (FIPS186-5) A5891 Curve - P-224, P-256, P-384, P-521
Hash Algorithm - SHA2-256, SHA2-384, SHA2-
512
FIPS 186-5
EDDSA KeyGen A5891 Curve - ED-25519 FIPS 186-5
EDDSA SigGen A5891 Curve - ED-25519 FIPS 186-5
EDDSA SigVer A5891 Curve - ED-25519 FIPS 186-5
HMAC-SHA-1 A5891 Key Length - Key Length: 112-512 Increment 8 FIPS 198-1
HMAC-SHA2-256 A5891 Key Length - Key Length: 112-512 Increment 8 FIPS 198-1
HMAC-SHA2-384 A5891 Key Length - Key Length: 112-1024 Increment
8
FIPS 198-1
HMAC-SHA2-512 A5891 Key Length - Key Length: 112-1024 Increment
8
FIPS 198-1
KAS-ECC-SSC Sp800-56Ar3 A5891 Domain Parameter Generation Methods - P-
224, P-256, P-384, P-521
Scheme -
fullUnified -
KAS Role - initiator, responder
onePassDh -
KAS Role - initiator, responder
onePassUnified -
KAS Role - initiator, responder
SP 800-56A
Rev. 3
KDA HKDF SP800-56Cr2 A5891 Derived Key Length - 256
Shared Secret Length - Shared Secret Length:
256
HMAC Algorithm - SHA2-256
SP 800-56C
Rev. 2
KDF ANS 9.63 (CVL) A5891 Hash Algorithm - SHA2-256
Key Data Length - Key Data Length: 512, 640
SP 800-135
Rev. 1
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Algorithm CAVP Cert Properties Reference
KDF SP800-108 A5891 KDF Mode - Counter
Supported Lengths - Supported Lengths: 8-
2040 Increment 8
SP 800-108
Rev. 1
RSA Decryption Primitive
Sp800-56Br2 (CVL)
A5891 Modulo - 2048, 3072, 4096 SP 800-56B
Rev. 2
RSA KeyGen (FIPS186-5) A5891 Key Generation Mode - probable
Modulo - 2048, 3072, 4096
Primality Tests - 2powSecStr
Private Key Format - crt
FIPS 186-5
RSA SigGen (FIPS186-5) A5891 Modulo - 2048, 3072, 4096
Signature Type - pkcs1v1.5
FIPS 186-5
RSA Signature Primitive (CVL) A5891 Modulo - 2048, 3072, 4096 FIPS 186-4
RSA SigVer (FIPS186-5) A5891 Modulo - 2048, 3072, 4096
Signature Type - pkcs1v1.5
FIPS 186-5
SHA-1 A5891 Message Length - Message Length: 0-65528
Increment 8
FIPS 180-4
SHA2-256 A5891 Message Length - Message Length: 0-65528
Increment 8
FIPS 180-4
SHA2-384 A5891 Message Length - Message Length: 0-65528
Increment 8
FIPS 180-4
SHA2-512 A5891 Message Length - Message Length: 0-65528
Increment 8
FIPS 180-4
Table 4: Approved Algorithms
Vendor-Affirmed Algorithms:
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The module supports the following vendor affirmed algorithms (refer to Table 5).
Name Properties Implementation Reference
CKG Key Type:Symmetric and
Asymmetric
Yubico Common
Cryptographic Library
NIST SP 800-133r2, Section 4 example 1,
Sections 5.1, 5.2, and 6.1
Table 5: Vendor-Affirmed Algorithms
Non-Approved, Allowed Algorithms:
The module supports ECDSA with non-NIST recommended curves: brainpool256r1, brainpool384r1, and
brainpool512r1. These curves are allowed per IG C.A.
The module also supports KAS with non-NIST recommended curves: brainpool256r1, brainpool384r1,
brainpool512r1. These curves are allowed per IG C.A.
Name Properties Implementation Reference
ECDSA Curve:brainpool256r1, brainpool384r1,
brainpool512r1
Yubico Common Cryptographic
Library
IG C.A
KAS Curve:brainpool256r1, brainpool384r1,
brainpool512r1
Yubico Common Cryptographic
Library
IG C.A
Table 6: Non-Approved, Allowed Algorithms
Non-Approved, Allowed Algorithms with No Security Claimed:
The module supports DES for internal integrity checks with no security claimed. In addition, the module supports
ECDH with no security claimed; this ECDH is to support the legacy PIN protocol 1 over directly connected USB
sessions. The ECDH implementation provides no security and all transmissions within the established session are
handled as plaintext. For this reason, the module only permits PIN protocol 1 use over a directly connected USB
session for which plaintext transmissions of PIN values permitted.
Name Caveat Use and Function
DES No security
claimed
For internal integrity checking use only
ECDH No security
claimed
For legacy use only, all information transmitted within the established sessions is
treated as plaintext over a directly connected path.
Table 7: Non-Approved, Allowed Algorithms with No Security Claimed
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Non-Approved, Not Allowed Algorithms:
Name Use and Function
AES (non-compliant) Supports the calculation of One-Time Passwords in the OTP functional unit.
HMAC (non-compliant) Supports the calculation of One-Time Passwords in the OTP functional unit.
Table 8: Non-Approved, Not Allowed Algorithms
2.6 SECURITY FUNCTION IMPLEMENTATIONS
Name Type Description Properties Algorithms
AKG AsymKeyPair-
KeyGen
RSA 2048, 3072,
4096, ECDSA P-
256, P-384, P-521
Standard:FIPS 186-5 CKG: ()
Key Type:
Symmetric and
Asymmetric
Counter DRBG:
(A5891)
RSA KeyGen
(FIPS186-5):
(A5891)
Modulo: 2048,
3072, 4096
ECDSA KeyGen
(FIPS186-5):
(A5891)
Curve: P-256, P-
384, P-521
EDDSA KeyGen:
(A5891)
Curve: ed25519
DEC BC-UnAuth Symmetric
Decryption
Standard:FIPS 197 AES-CBC: (A5891)
Key Size: 128, 192,
256
AES-ECB: (A5891)
Key Size: 128, 192,
256
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Name Type Description Properties Algorithms
ECSP UNK Signature
Generation
Primitive
Standard:FIPS 186-5 ECDSA SigGen
(FIPS186-5):
(A5891)
Curve: P-256, P-
384, P-521,
brainpool256r1,
brainpool384r1,
brainpool512r1
ENC BC-Auth Symmetric
Encryption
Standard:FIPS 197 AES-CBC: (A5891)
Key Size: 128, 192,
256
AES-ECB: (A5891)
Key Size: 128, 192,
256
ESV ENT-ESV SP800-90B Physical
Entropy Source
Standard:SP800-90B
KAS-KG KAS-KeyGen Key Generation Standard:SP800-56Ar3 KAS-ECC-SSC
Sp800-56Ar3:
(A5891)
KAS-PP2 KAS-Full NIST SP 800-
56Arev3 KAS-ECC
Per IG D.F Scenario
2 path (2). CTAP
Session (Pin
Protocol 2)
Standard:SP800-56Ar3,
SP800-56Cr2
IG:IG D.F Scenario 2
path (2), split
Key Confirmation:No
Key Derivation:KDA
(separately tested)
Caveat:Key
establishment
methodology provides
128 bits of security
strength
KAS-ECC-SSC
Sp800-56Ar3:
(A5891)
Curve: P-256
KDA HKDF SP800-
56Cr2: (A5891)
KAS-SCP11 KAS-Full SCP11 Security
Domain
implementation
Standard:SP800-56Ar3
Implementation:SCP11
Security Domain
KAS-ECC-SSC
Sp800-56Ar3:
(A5891)
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Name Type Description Properties Algorithms
using SP800-135r1
ANSI X9.63 KDF
YubiHSM-Auth
implementation using
SP800-135r1 ANSI
X9.63 KDF, Global
Platform GPC v2.3
Amendment F v1.2.1
SCP11
IG:IG D.F Scenario 2
path (2), split
Key Confirmation:No
Key Derivation:KDA
(separately tested)
Caveat:Key
establishment
methodology provides
128 bits of security
strength
Scheme: (2e,2s),
(1e,2s)
Curve: P-256
KDF ANS 9.63:
(A5891)
KBKDF KBKDF Key-Based Key
Derivation CMAC-
AES128 (SCP03 and
YubiHSM-Auth).
Only used as part
of session
establishment.
Standard:SP800-108
Implementation:Global
Platform GPC 2.3
Amendment D v1.2
SCP03
KDF SP800-108:
(A5891)
KTS-CBC-CMAC KTS-Wrap Global Platform
GPC 2.3
Amendment D v1.2
SCP03 Global
Platform GPC v2.3
Amendment F v1.4
SCP11, SP800-
56Ar3
Standard:SP800-38F
IG D.G:Approved
method from IG D.G
Caveat:Key
establishment
methodology provides
128 to 256 bits of
security strength
AES-CBC: (A5891)
Key Size: 128, 192,
256
AES-CMAC:
(A5891)
Key Size: 128, 192,
256
KTS-CBC-HMAC KTS-Wrap FIDO Client to
Authenticator
Protocol (CTAP) 2.1
Pin protocol 2
Standard:SP800-38F
IG D.G:Approved
method from IG D.G
Caveat:Key
establishment
methodology provides
AES-CBC: (A5891)
Key Size: 128, 192,
256
HMAC-SHA2-256:
(A5891)
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Name Type Description Properties Algorithms
128 to 256 bits of
security strength
Key Size: 128, 192,
256
KTS-CCM KTS-Wrap FIDO wrapping key Standard:SP800-108,
Global Platform GPC
2.3 Amendment D v1.2
SCP03
IG D.G:Approved
method from IG D.G
Caveat:Key
establishment
methodology provides
128 to 256 bits of
security strength
AES-CCM: (A5891)
Key Size: 128, 192,
256
MAC MAC Keyed MAC Standard:FIPS 198-2 AES-CMAC:
(A5891)
HMAC-SHA-1:
(A5891)
HMAC-SHA2-256:
(A5891)
HMAC-SHA2-384:
(A5891)
HMAC-SHA2-512:
(A5891)
PKV AsymKeyPair-
PubKeyVal
Public key
validation
Standard:SP800-56Ar3,
FIPS186-5
ECDSA KeyGen
(FIPS186-5):
(A5891)
KAS-ECC-SSC
Sp800-56Ar3:
(A5891)
RAND DRBG Random Number
Generation
Standard:SP800-90A Counter DRBG:
(A5891)
RSADP UNK RSA Decryption
Primitive (PKCS#1
Standard:SP800-56Br2 RSA Decryption
Primitive Sp800-
56Br2: (A5891)
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Name Type Description Properties Algorithms
v2.1). Key size 2048
(PIV raw).
Modulo: 2048,
3072, 4096
RSASP UNK RSA Signature
Primitive
Standard:FIPS 186-5 RSA Signature
Primitive: (A5891)
Modulo: 2048,
3072, 4096
SHS SHA Message Digest Standard:FIPS 180 SHA-1: (A5891)
SHA2-256: (A5891)
SHA2-384: (A5891)
SHA2-512: (A5891)
SSC KAS-SSC Shared Secret
Calculation
Standard:SP800-56Ar3 KAS-ECC-SSC
Sp800-56Ar3:
(A5891)
Scheme: (1e,1s,
ECC CDH)
Type: Co-factor
One-Pass Diffie
Hellman
Curve: P-256, P-
384, P-521,
brainpool256r1,
brainpool384r1,
brainpool512r1
SigGen DigSig-SigGen Signature
Generation
Standard:FIPS 186-5 RSA SigGen
(FIPS186-5):
(A5891)
Modulo: 2048,
3072, 4096
ECDSA SigGen
(FIPS186-5):
(A5891)
Curve: P-256, P-
384, P-521,
brainpool256r1,
brainpool384r1,
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Name Type Description Properties Algorithms
brainpool512r1
EDDSA SigGen:
(A5891)
Curve: ed25519
SigVer DigSig-SigVer Signature
Verification
Standard:FIPS 186-5 RSA SigVer
(FIPS186-5):
(A5891)
Modulo: 2048,
3072, 4096
ECDSA SigVer
(FIPS186-5):
(A5891)
Curve: P-256, P-
384, P-521,
brainpool256r1,
brainpool384r1,
brainpool512r1
EDDSA SigVer:
(A5891)
Curve: ed25519
SymKG CKG Symmetric Key
Generation
Standard:SP800-133r2 Counter DRBG:
(A5891)
CKG: ()
Key Type:
Symmetric and
Asymmetric
Table 9: Security Function Implementations
2.7 ALGORITHM SPECIFIC INFORMATION
The module utilizes only approved algorithms that are tested and validated under the Cryptographic Algorithm
Validation Program (CAVP).
Compliance to SP 800-56Ar3 assurances:
For KAS-ECC, the module satisfies IG D.F Scenario 2 path (2). The key derivation functions comply with NIST SP 800-
56Cr2 (i.e., KDA HKDF SP 800-56Cr2 (Cert. #A5891)) and ANS 9.63 (i.e., KDF ANS 9.63 (Cert. #A5891). Furthermore,
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the module obtained the appropriate assurances, as required in Sections 5.6.2 of NIST SP 800-56Ar3. Full public
key validation (NIST SP 800-56Ar3 Section 5.6.2.3.3) is implemented. No key confirmation is implemented.
Limited use of SHA-1:
The use of SHA-1 (Cert. #A5891) is restricted within the module to non-digital signature applications. SHA-1 is
solely used within HMAC-SHA-1 (Cert. #A5891).
2.8 RBG AND ENTROPY
The module incorporates a NIST SP 800-90A CTR-DRBG (Cert. #A5891) that is seeded from the module’s NIST SP
800-90B validated entropy source. The unmodified output of the DRBG is used for generating cryptographic key
material. The DRBG is instantiated anew every power-on. The threshold for reseeding is monitored to not exceed
248
per SP 800-90A.
Cert
Number
Vendor Name
E196 Infineon Technologies AG
Table 10: Entropy Certificates
Name Type Operational
Environment
Sample
Size
Entropy
per
Sample
Conditioning
Component
Infineon 16-bit Security Controller
M7893B11 Entropy Source
Physical M7893B11 8 bits 2.55928
bits
Non-Vetted
Conditioning
Table 11: Entropy Sources
2.9 KEY GENERATION
The module supports the generation of cryptographic keys and components with a security strength of 256-bits.
2.10 KEY ESTABLISHMENT
The module supports key establishment using KAS with a supported security strength of 128 or 256-bits,
depending on the selection of key sizes utilized. The module supports key transport with a supported security
strength of 128 or 256-bits, depending on the selection of key sizes utilized.
2.11 INDUSTRY PROTOCOLS
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The module supports the Secure Channel Protocols SCP03 & SCP11 for the establishment of ephemeral, protected
communication sessions.
3 CRYPTOGRAPHIC MODULE INTERFACES
3.1 PORTS AND INTERFACES
The module incorporates physical ports and logical interfaces. The physical ports are defined within Table 12
below:
Physical Port Logical
Interface(s)
Data That Passes
I2C I/O pins Control Input
Status Output
Commands, Return Codes, and Error Status
Interface Select pins Control Input Interface selection
LED Interface pins Status Output Emits power to an LED, if attached
NFC Interface pins Data Input
Data Output
Control Input
Status Output
SSPs, User data, Commands, Return Codes, and Error Status
Power Interface pins Power N/A
Touch Button Interface pins Control Input Physical presence indicator
USB pins (D+/D-) Data Input
Data Output
Control Input
Status Output
SSPs, User data, Commands, Return Codes, and Error Status
Table 12: Ports and Interfaces
4 ROLES, SERVICES, AND AUTHENTICATION
4.1 AUTHENTICATION METHODS
The module supports authentication methods for the Cryptographic Officer (CO) role. The authentication method
of both Crypto Officer and User is the password-based authentication that the module performs Memorized Secret
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and Single-Factor Cryptographic Device described in NIST SP 800-140E and SP 800-63B-4 (refer to Sections 3.1.1,
3.1.2, and 3.1.6). This role has separate authentication methods as indicated in Table 13. Section 11.1 describes
the procedure by which an operator is to perform authentication as part of the module initialization process. The
module supports three authentication methods: PIN verification, knowledge of a shared secret, and possession of
a private key.
Method
Name
Description Security
Mechanism
Strength Each Attempt Strength per Minute
PIN
verification
PIN
verification
Comparison of
a 6 byte string
A minimum 6 byte (48 bit)
binary string has a
probability that a random
attempt will succeed or a
false acceptance will occur
of 1/2^48 which is less than
1/1,000,000.
Each authentication attempt
takes approximately 60 ms
which allows a maximum of
1000 attempts per minute.
Therefore, the probability of
successfully authenticating to
the module within one minute
through random attempts is
1000/2^48, which is less than
1/100,000.
Knowledge
of a shared
secret
Knowledge
of a shared
secret
Cryptographic
Software
The shared secret is either
a 128, 192, or 256-bit AES
key or a minimum length
112 bits HMAC key. The
probability that a random
attempt will succeed or a
false acceptance will occur
is at most 1/2^112 which is
less than 1/1,000,000.
Authentication attempts are
limited to 6,000 per minute due
to performance constraints.
Therefore, the probability of
successfully authenticating to
the module within one minute
through random attempts is
6,000/2^112, which is less than
1/100,000.
Possession
of Private
Key
Knowledge
of the static
private key
Cryptographic
Software
The KAS-ECC private key
uses curve P-256, which has
a security strength of 128
bits. The probability that a
random attempt will
succeed or a false
acceptance will occur is
1/2^128 which is less than
1/1,000,000.
Authentication attempts are
limited to 6,000 per minute due
to performance constraints.
Therefore, the probability of
successfully authenticating to
the module within one minute
through random attempts is
6,000/2^128, which is less than
1/100,000.
Table 13: Authentication Methods
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4.2 ROLES
The module supports a Cryptographic Officer (CO), a User, and an unauthenticated role. The CO is responsible for
configuring SSPs and resetting User credentials. The User performs cryptographic operations and utilizes the
module as an authenticator. The unauthenticated role has access to respond to challenges, read non-security-
relevant information, perform self-tests, and reset services only.
Name Type Operator Type Authentication Methods
Crypto Officer Role CO PIN verification
Knowledge of a shared secret
Possession of Private Key
User Role User PIN verification
Knowledge of a shared secret
Unauthenticated Role N/A None
Table 14: Roles
4.3 APPROVED SERVICES
The module supports six functional units, each of which provides access to a unique set of services: PIV, OATH,
OpenPGP, FIDO, Security Domain, and YubiHSM Auth. All Approved services and non-Approved services are
accessible over both USB and NFC interfaces.
Please note that all services can be performed over a Secure Channel (SCP03 or SCP11) with the exception of:
− FIDO services conducted directly over USB
− Services that establish the Secure Channel
o Initialize Update service and External Authenticate service that establish the SCP03 session
o Perform Security operation service, Internal Authenticate service and Mutual Authenticate
service that establish the SCP11 session
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Activate
Applet -
OpenPGP
Activate
OpenPGP
applet with
factory
defaults.
Zeroization.
return
code
0x9000
none success/error ENC
DEC
MAC
Unauthenticat
ed
- Secure
Channel
Session Keys:
E
- Asymmetric
Public Keys: Z
- Asymmetric
Private Keys: Z
- KAS Private
Keys: Z
- KAS Public
Keys: Z
- PINs: Z
Attest -
OpenPGP
Generate
attestation
for an
internally
generated
key
return
code
0x9000
Key ID success/error RAND
SigGen
KTS-
CBC-
CMAC
ENC
DEC
MAC
User
- DRBG State:
G,E
- Attestation
Key: E
- Asymmetric
Public Keys: R
- KAS Public
Keys: R
- Secure
Channel
Session Keys:
E
Attest - PIV Generate an
attestation
for an
internally
generated
key
return
code
0x9000
Key ID x509 attestation SigGen
RAND
KTS-
CBC-
CMAC
ENC
Unauthenticat
ed
- DRBG State:
G,E
- Attestation
Key: E
- Asymmetric
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
DEC
MAC
Public Keys: R
- KAS Public
Keys: R
- Secure
Channel
Session Keys:
E
Authenticat
or Config -
FIDO
Set and
retrieve
authenticato
r
configuration
return
code
0x9000
configuration configuration MAC
ENC
DEC
RAND
SymKG
User
- DRBG State:
G,E
- CTAP PIN
token: G,E,Z
- Secure
Channel
Session Keys:
E
Authenticat
or Select -
FIDO
Identify
authenticato
r
return
code
0x9000
none success/error ENC
DEC
MAC
Unauthenticat
ed
- Secure
Channel
Session Keys:
E
Calculate -
OATH
Calculate the
code for an
OATH entry
return
code
0x9000
OATH credential
ID
HMAC response ENC
DEC
MAC
RAND
Crypto Officer
- OATH Seed
Key: E
- Secure
Channel
Session Keys:
E
- DRBG State:
G,E
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Calculate -
YubiHSM
Auth
User
Authenticate
return
code
0x9000
authentication
challenge or
public key
session keys KAS-
SCP11
KTS-
CBC-
CMAC
KBKDF
PKV
RAND
ENC
DEC
MAC
User
- KAS Private
Keys: E,Z
- KAS Public
Keys: W,E,Z
- DRBG State:
G,E
- Secure
Channel
Session Keys:
R,E,G
- PINs: W,E
- Secure
Channel
Authenticatio
n Keys: E
Calculate All
- OATH
Calculate
code for all
entries
return
code
0x9000
none HMAC responses ENC
DEC
MAC
RAND
Crypto Officer
- OATH Seed
Key: E
- Secure
Channel
Session Keys:
E
- DRBG State:
G,E
Change
Managemen
t Key - PIV
Change
management
key
return
code
0x9000
new
management
key
success/error ENC
DEC
MAC
KTS-
CBC-
CMAC
Crypto Officer
- PIV
Management
Auth Key: W
- Secure
Channel
Session Keys:
E
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Change PIN -
PIV
Change user
PIN with
known PIN
return
code
0x9000
old and new PIN success/error ENC
DEC
MAC
User
- PINs: W,E
- Secure
Channel
Session Keys:
E
Change PIN -
YubiHSM
Auth
Update PIN return
code
0x9000
old PIN and new
PIN
success/error ENC
DEC
MAC
Crypto Officer
- PINs: E,W
- Secure
Channel
Session Keys:
E
Change PUK
- PIV
Change PIN
unlock code
return
code
0x9000
old and new PUK success/error ENC
DEC
MAC
Crypto Officer
- PINs: W,E
- Secure
Channel
Session Keys:
E
Change PW1
- OpenPGP
Update user
PIN
return
code
0x9000
old PW1 and
new PW1
success/error ENC
DEC
MAC
User
- PINs: W,E
- Secure
Channel
Session Keys:
E
Change PW3
- OpenPGP
Update
admin PIN
return
code
0x9000
old PW3 and
new PW3
success/error ENC
DEC
MAC
Crypto Officer
- PINs: W,E
- Secure
Channel
Session Keys:
E
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Change
Retry
Counters -
PIV
Set retry
counter for
PINs
return
code
0x9000
new counters success/error ENC
DEC
MAC
Crypto Officer
- PINs: Z
- Secure
Channel
Session Keys:
E
Close
Session
Closes the
secure
session
None None None None Crypto Officer
- Secure
Channel
Session Keys:
Z
Compute
Digital
Signature
Primitive -
OpenPGP
Perform
signature
primitive
return
code
0x9000
hash of message
to sign
signature RAND
ECSP
RSASP
ENC
DEC
MAC
User
- DRBG State:
G,E
- Asymmetric
Private Keys: E
- Secure
Channel
Session Keys:
E
Credential
Managemen
t - FIDO
Listing
credentials
and deleting
credentials
return
code
0x9000
credential ID,
relying party ID
list of credentials,
which include public
keys, or relying
parties
MAC
KTS-
CBC-
CMAC
ENC
DEC
RAND
User
- CTAP PIN
token: E
- Asymmetric
Private Keys: Z
- Asymmetric
Public Keys:
R,Z
- CTAP Offline
Key: E
- Secure
Channel
Session Keys:
E
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
- DRBG State:
G,E
Decipher -
OpenPGP
EC-DH
shared secret
calculation
return
code
0x9000
public key for
KAS
Shared secret RAND
SSC
PKV
KTS-
CBC-
CMAC
ENC
DEC
MAC
User
- DRBG State:
G,E
- KAS Private
Keys: E
- Shared
Secret: G,E,R
- KAS Public
Keys: W,E
- Secure
Channel
Session Keys:
E
Delete -
OATH
Remove an
OATH entry
return
code
0x9000
OATH credential
ID
success/error ENC
DEC
MAC
Crypto Officer
- OATH Seed
Key: Z
- Secure
Channel
Session Keys:
E
Delete Key -
PIV
Delete an
asymmetric
key
return
code
0x9000
Key ID success/error ENC
DEC
MAC
Crypto Officer
- Asymmetric
Private Keys: Z
- Attestation
Key: Z
- KAS Private
Keys: Z
- Asymmetric
Public Keys: Z
- KAS Public
Keys: Z
- Secure
Channel
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Session Keys:
E
Delete Key -
SD
Delete key
set
return
code
0x9000
Key ID success/error ENC
DEC
MAC
Crypto Officer
- Secure
Channel
Authenticatio
n Keys: Z
- Secure
Channel
Sensitive Data
Key: Z
- KAS Private
Keys: Z
- KAS Public
Keys: Z
- Asymmetric
Public Keys: Z
- Secure
Channel
Session Keys:
E
Delete Keys
- YubiHSM
Auth
Delete keys return
code
0x9000
Key ID success/error ENC
DEC
MAC
Crypto Officer
- KAS Private
Keys: Z
- KAS Public
Keys: Z
- PINs: W,E,Z
- Secure
Channel
Session Keys:
E
- Secure
Channel
Authenticatio
n Keys: Z
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Device
Configuratio
n
Select a
functional
unit and
retrieve or
configure
non-security
relevant
device
information
return
code
0x9000
request for
device
configuration
current device
configuration
ENC
DEC
MAC
Unauthenticat
ed
- Secure
Channel
Session Keys:
E
External
Authenticate
- SD
Complete
Session
Establishmen
t
return
code
0x9000
finishing
authentication
data
authentication data MAC Unauthenticat
ed
- Secure
Channel
Session Keys:
E
General
AUTH
Decrypt -
PIV
Decrypt
input data.
This service
returns an
error if the
decryption
key is not an
RSA key.
return
code
0x9000
data to be
decrypted, slot
number for
decryption key
success/error/decryp
ted data
RAND
RSADP
ENC
DEC
MAC
User
- DRBG State:
G,E
- Asymmetric
Private Keys: E
- Secure
Channel
Session Keys:
E
General
AUTH Key
Agreement -
PIV
Perform key
agreement.
This service
returns an
error if the
key in the
slot is not an
ECC key.
return
code
0x9000
partner's public
key, slot number
for the module's
KAS private key
success/error/shared
secret
RAND
PKV
SSC
KTS-
CBC-
CMAC
ENC
DEC
MAC
User
- DRBG State:
G,E
- KAS Private
Keys: E
- KAS Public
Keys: W,E
- Shared
Secret: G,E,R
- Secure
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Channel
Session Keys:
E
General
AUTH
Managemen
t
Authenticati
on - PIV
Authenticate
to the applet
using the
Management
Auth Key.
return
code
0x9000
applet
authentication
data,
challenge/respo
nse
challenge/response,
success/failure
RAND
ENC
DEC
MAC
Unauthenticat
ed
- DRBG State:
G,E
- PIV
Management
Auth Key: E
- Secure
Channel
Session Keys:
E
General
AUTH Sign -
PIV
Sign digest
data
return
code
0x9000
digest to be
signed, slot
number for
signing key
success/error/signed
data
RAND
RSASP
ECSP
ENC
DEC
MAC
User
- DRBG State:
G,E
- Asymmetric
Private Keys: E
- Secure
Channel
Session Keys:
E
Generate
Asymmetric
Key Pair -
OpenPGP
Generate
asymmetric
key pair
return
code
0x9000
Key ID public key RAND
AKG
PKV
KAS-KG
KTS-
CBC-
CMAC
ENC
DEC
MAC
Crypto Officer
- DRBG State:
G,E
- Asymmetric
Private Keys:
G,E
- KAS Private
Keys: G,E
- Asymmetric
Public Keys:
G,R,E
- KAS Public
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Keys: G,R,E
- Secure
Channel
Session Keys:
E
Generate
Key - PIV
Generate
asymmetric
key pair
return
code
0x9000
slot number,
parameters, PIN
policy
public key RAND
PKV
AKG
KAS-KG
KTS-
CBC-
CMAC
ENC
DEC
MAC
Crypto Officer
- DRBG State:
G,E
- Asymmetric
Private Keys:
G,E
- KAS Private
Keys: G,E
- Asymmetric
Public Keys:
G,R,E
- KAS Public
Keys: G,R,E
- Secure
Channel
Session Keys:
E
Generate
Key Pair - SD
Generate
SCP11
keypair
return
code
0x9000
Key ID public key KAS-KG
PKV
KTS-
CBC-
CMAC
ENC
DEC
MAC
RAND
Crypto Officer
- KAS Private
Keys: G,Z
- KAS Public
Keys: G,R,Z
- DRBG State:
G,E
Get
Assertion -
FIDO
Use
credential
return
code
0x9000
keyhandle
(potentially
signature RAND
KTS-
CCM
KTS-
User
- DRBG State:
G,E
- Wrapping
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
wrapped key),
challenge
CBC-
CMAC
SigGen
ENC
DEC
MAC
Key: E
- Asymmetric
Private Keys:
E,W
- CTAP Offline
Key: E
- CTAP PIN
token: E
- Secure
Channel
Session Keys:
E
Get
Challenge -
YubiHSM
Auth
Get a
challenge for
authenticatio
n
return
code
0x9000
none Challenge or public
key
RAND
KAS-KG
PKV
KTS-
CBC-
CMAC
ENC
DEC
MAC
User
- DRBG State:
G,E
- KAS Private
Keys: G,Z
- KAS Public
Keys: G,R,Z
- PINs: W,E
- Secure
Channel
Session Keys:
E
Get Data -
SD
Get
metadata
return
code
0x9000
none metadata, X.509
certificate
SigGen
KTS-
CBC-
CMAC
ENC
DEC
MAC
RAND
Unauthenticat
ed
- Attestation
Key: E
- Asymmetric
Public Keys: R
- KAS Public
Keys: R
- Secure
Channel
Session Keys:
E
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
- DRBG State:
G,E
Get
Information-
FIDO
Device
information
return
code
0x9000
none metadata ENC
DEC
MAC
Unauthenticat
ed
- Secure
Channel
Session Keys:
E
Get
Metadata -
PIV
Get
metadata
return
code
0x9000
metadata of
stored keys
algorithm, public
keys and policies of
keys
KTS-
CBC-
CMAC
ENC
DEC
MAC
Unauthenticat
ed
- Asymmetric
Public Keys: R
- KAS Public
Keys: R
- Secure
Channel
Session Keys:
E
Get Pubkey -
YubiHSM
Auth
Get a public
key of an
Authenticati
on Key
return
code
0x9000
Key ID public key of
Authentication Key
PKV
KTS-
CBC-
CMAC
ENC
DEC
MAC
RAND
Unauthenticat
ed
- KAS Public
Keys: G,R
- Secure
Channel
Session Keys:
E
- DRBG State:
G,E
Get Retry
Count -
YubiHSM
Auth
Specify the
number of
Login
attempts
remaining
return
code
0x9000
none number of retries
remaining
ENC
DEC
MAC
Unauthenticat
ed
- Secure
Channel
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Session Keys:
E
Get Serial -
PIV
Get serial
number
return
code
0x9000
none serial number ENC
DEC
MAC
Unauthenticat
ed
- Secure
Channel
Session Keys:
E
Get Version
- OpenPGP
Get firmware
version
return
code
0x9000
none version ENC
DEC
MAC
Unauthenticat
ed
- Secure
Channel
Session Keys:
E
Get Version
- PIV
Get firmware
version
return
code
0x9000
none version number ENC
DEC
MAC
Unauthenticat
ed
- Secure
Channel
Session Keys:
E
Get Version
- YubiHSM
Auth
Get FW
version
return
code
0x9000
none version number ENC
DEC
MAC
Unauthenticat
ed
- Secure
Channel
Session Keys:
E
Import
Asymmetric
Key -
OpenPGP
Import
asymmetric
private key
return
code
0x9000
asymmetric
private key
success/error RAND
PKV
KTS-
CBC-
CMAC
ENC
Crypto Officer
- Asymmetric
Private Keys:
W,E
- KAS Private
Keys: W,E
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
DEC
MAC
- Asymmetric
Public Keys:
G,E
- KAS Public
Keys: G,E
- DRBG State:
G,E
- Secure
Channel
Session Keys:
E
Import Key -
PIV
Import
asymmetric
private key
return
code
0x9000
asymmetric
private key
success/error RAND
PKV
KTS-
CBC-
CMAC
ENC
DEC
MAC
Crypto Officer
- Asymmetric
Private Keys:
W,E
- KAS Private
Keys: W,E
- Asymmetric
Public Keys:
G,E
- KAS Public
Keys: G,E
- Attestation
Key: W,E
- DRBG State:
G,E
- Secure
Channel
Session Keys:
E
Initialize
Update - SD
Create
Secure
Channel
Session
return
code
0x9000
initialization
authentication
challenge
authentication data KBKDF
RAND
Unauthenticat
ed
- Secure
Channel
Authenticatio
n Keys: E
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
- Secure
Channel
Session Keys:
G
- DRBG State:
G,E
Internal
Authenticate
- OpenPGP
Perform
internal
authenticatio
n (signature
primitive)
return
code
0x9000
hash of message
to sign
signature RAND
ECSP
RSASP
ENC
DEC
MAC
User
- DRBG State:
G,E
- Asymmetric
Private Keys: E
- Secure
Channel
Session Keys:
E
Internal
Authenticate
- SD
Used for
SCP11-b
return
code
0x9000
other party
ephemeral key
internal ephemeral
public key
KAS-
SCP11
KAS-KG
PKV
RAND
Unauthenticat
ed
- KAS Private
Keys: G,E,Z
- KAS Public
Keys: G,R,E,Z
- Secure
Channel
Session Keys:
G
- DRBG State:
G,E
LargeBlob -
FIDO
Store and
retrieve data
return
code
0x9000
encrypted data encrypted data MAC
ENC
DEC
RAND
User
- DRBG State:
G,E
- CTAP PIN
token: E
- Secure
Channel
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Session Keys:
E
List - OATH List all the
names of the
OATH entries
return
code
0x9000
none list of all OATH keys ENC
DEC
MAC
Crypto Officer
- Secure
Channel
Session Keys:
E
List -
YubiHSM
Auth
List the
credential
names
return
code
0x9000
none list of keys ENC
DEC
MAC
Unauthenticat
ed
- Secure
Channel
Session Keys:
E
Make
Credential -
FIDO
Create a new
FIDO
credential
(resident or
transient)
return
code
0x9000
credential
specification
public key,
attestation data and
keyhandle
(potentially wrapped
key)
RAND
KTS-
CCM
KTS-
CBC-
CMAC
SigGen
AKG
PKV
ENC
DEC
MAC
User
- DRBG State:
G,E
- Wrapping
Key: E
- Asymmetric
Private Keys:
G,R
- Attestation
Key: E
- CTAP PIN
token: E
- Asymmetric
Public Keys:
G,R
- CTAP Offline
Key: E
- Secure
Channel
Session Keys:
E
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Move Key -
PIV
Move an
asymmetric
key
return
code
0x9000
Key ID success/error ENC
DEC
MAC
Crypto Officer
- Secure
Channel
Session Keys:
E
Mutual
Authenticate
- SD
Used for
SCP11-a
(2e,2s) &
SCP11-c
(1e,2s)
return
code
0x9000
other party
ephemeral key
internal ephemeral
public key
KAS-
SCP11
KAS-KG
PKV
RAND
Unauthenticat
ed
- KAS Private
Keys: G,E,Z
- KAS Public
Keys: G,R,E,Z
- Secure
Channel
Session Keys:
G
- DRBG State:
G,E
PIN Service -
FIDO
Creating,
updating,
and
validating
PIN
return
code
0x9000
PIN, ephemeral
KAS Public Key
encrypted PIN Token RAND
MAC
KAS-PP2
KTS-
CBC-
HMAC
KTS-
CBC-
CMAC
SymKG
SHS
KAS-KG
PKV
ENC
DEC
User
- DRBG State:
G,E
- PINs: W,E
- CTAP PIN
token: G,R,Z
- CTAP Session
Keys: E,G
- KAS Private
Keys: G,R,Z
- KAS Public
Keys: R,W,E,G
- Secure
Channel
Session Keys:
E
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Perform
Security
Operation -
SD
Initial step
for SCP11
return
code
0x9000
static public key
for SCP11
success/error SigVer
PKV
RAND
Unauthenticat
ed
- KAS Public
Keys: W,Z
- DRBG State:
G,E
- Asymmetric
Public Keys:
W,E,Z
Power On Power
Cycling
services
availabl
e
none none SymKG
ESV
Unauthenticat
ed
- Entropy
Input : G,E
- DRBG Seed :
G,E
- CTAP Offline
Key: G
- Wrapping
Key: G
- DRBG State:
G,E
Put - OATH Add a new
OATH entry
return
code
0x9000
new OATH Seed
key
success/error KTS-
CBC-
CMAC
ENC
DEC
MAC
Crypto Officer
- OATH Seed
Key: W
- Secure
Channel
Session Keys:
E
Put Key - SD Load
Authenticati
on Keys
return
code
0x9000
Secure Channel
Authentication
Keys, Public Key
success/error KTS-
CBC-
CMAC
PKV
ENC
DEC
Crypto Officer
- Secure
Channel
Authenticatio
n Keys: W,Z
- Secure
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
MAC
RAND
Channel
Sensitive Data
Key: W,E,Z
- KAS Private
Keys: W,E,Z
- KAS Public
Keys: G,E,Z
- Asymmetric
Public Keys:
W,E,Z
- Secure
Channel
Session Keys:
E
- DRBG State:
G,E
Put Keys -
YubiHSM
Auth
Load keys
and
associated
PIN or
generate
keys
return
code
0x9000
Authentication
Key and PIN
success/error RAND
KTS-
CBC-
CMAC
KAS-KG
PKV
ENC
DEC
MAC
Crypto Officer
- KAS Private
Keys: E,G
- KAS Public
Keys: G,E
- PINs: W,E
- DRBG State:
G,E
- Secure
Channel
Session Keys:
E
- Secure
Channel
Authenticatio
n Keys: W
Read Data
From
Protected
Read
protected
user data
return
code
0x9000
Container ID data ENC
DEC
MAC
User
- Secure
Channel
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Containers -
PIV
Session Keys:
E
Read Data
From
Unprotected
Containers -
PIV
Read user
data
return
code
0x9000
Container ID data ENC
DEC
MAC
Unauthenticat
ed
- Secure
Channel
Session Keys:
E
Read
Protected
Data For
Admin -
OpenPGP
Read data
objects only
available to
admin
return
code
0x9000
Data Object ID data ENC
DEC
MAC
Crypto Officer
- Secure
Channel
Session Keys:
E
Read
Protected
Data For
User -
OpenPGP
Read data
objects only
available to
user
return
code
0x9000
Data Object ID data ENC
DEC
MAC
User
- Secure
Channel
Session Keys:
E
Read Public
Key -
OpenPGP
Read public
key
return
code
0x9000
Key ID public key KTS-
CBC-
CMAC
ENC
DEC
MAC
Unauthenticat
ed
- Secure
Channel
Session Keys:
E
- Asymmetric
Public Keys: R
- KAS Public
Keys: R
Read
Unprotected
Data Object
- OpenPGP
Read all
unprotected
data
return
code
0x9000
Data Object ID data, X.509
certificate
ENC
DEC
MAC
Unauthenticat
ed
- Secure
Channel
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Session Keys:
E
- Asymmetric
Public Keys: R
- KAS Public
Keys: R
Rename -
OATH
Update the
Name of an
OATH
credential
entry
return
code
0x9000
new and old
OATH Credential
ID
success/error ENC
DEC
MAC
Crypto Officer
- Secure
Channel
Session Keys:
E
Reset - FIDO Zeroization return
code
0x9000
none success/error ENC
DEC
MAC
Unauthenticat
ed
- Asymmetric
Private Keys: Z
- Wrapping
Key: G,Z
- CTAP Offline
Key: G,Z
- PINs: Z
- Secure
Channel
Session Keys:
E
Reset -
OATH
Delete all
OATH
credentials
and set the
applet to the
factory
defaults.
Zeroization.
return
code
0x9000
none success/error ENC
DEC
MAC
Unauthenticat
ed
- OATH Seed
Key: Z
- OATH
Management
Auth Key: Z
- Secure
Channel
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Session Keys:
E
Reset - PIV Reset PIV
card state
and delete
all stored
information
Zeroization
return
code
0x9000
none success/error ENC
DEC
MAC
Unauthenticat
ed
- Asymmetric
Private Keys: Z
- KAS Private
Keys: Z
- Asymmetric
Public Keys: Z
- KAS Public
Keys: Z
- PINs: Z
- PIV
Management
Auth Key: Z
- Secure
Channel
Session Keys:
E
Reset -
YubiHSM
Auth
Zeroization return
code
0x9000
none success/error ENC
DEC
MAC
Unauthenticat
ed
- KAS Private
Keys: Z
- KAS Public
Keys: Z
- Secure
Channel
Session Keys:
E
- Secure
Channel
Authenticatio
n Keys: Z
- PINs: Z
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Select - SD Select SD
Application
return
code
0x9000
SD AID SD PIX None Unauthenticat
ed
Select
Applet -
FIDO
Select FIDO
applet
return
code
0x9000
FIDO AID version string RAND
KAS-KG
PKV
Unauthenticat
ed
- DRBG State:
G,E
- KAS Private
Keys: G,E
- KAS Public
Keys: G,E
Select
Applet -
OATH
Select OATH
Applet
return
code
0x9000
OATH AID version, ID,
authentication
challenge
RAND Unauthenticat
ed
- DRBG State:
G,E
Select
Applet -
OpenPGP
Select
OpenPGP
applet
return
code
0x9000
OpenPGP AID OpenPGP PIX None Unauthenticat
ed
Select
Applet - PIV
Select PIV
applet
return
code
0x9000
PIV Applet ID
(AID)
PIV Proprietary
Identifier Extension
(PIX)
None Unauthenticat
ed
Select
Applet -
YubiHSM
Auth
Select
YubiHSM
Auth
Application
return
code
0x9000
YubiHSM Auth
AID
version None Unauthenticat
ed
Set Code -
OATH
Set or
update a
Management
Auth Key
return
code
0x9000
new OATH
Management
Auth Key
authentication data
for new key
KTS-
CBC-
CMAC
ENC
Crypto Officer
- OATH
Management
Auth Key: W,E
- Secure
Channel
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
DEC
MAC
Session Keys:
E
Set Key
Attribute -
OpenPGP
Specify/Chan
ge a key
container
type (RSA or
EC) and
length. If a
key's type is
changed, it
will zeroize
the existing
key.
return
code
0x9000
algorithm success/error ENC
DEC
MAC
Crypto Officer
- Asymmetric
Private Keys: Z
- Asymmetric
Public Keys: Z
- Secure
Channel
Session Keys:
E
Set PIN
Retries -
OpenPGP
Set retry
limit for
PW1, PW3
and reset-
code
return
code
0x9000
new retry limit success/error ENC
DEC
MAC
Crypto Officer
- Secure
Channel
Session Keys:
E
Terminate
Applet -
OpenPGP
Terminate
OpenPGP
applet and
delete all
stored data
return
code
0x9000
none success/error ENC
DEC
MAC
Unauthenticat
ed
- Secure
Channel
Session Keys:
E
Unblock PIN
(reset retry
counter) -
PIV
Reset retry
counter and
set new user
PIN using
known
unlock code
return
code
0x9000
PUK and new
PIN
success/error ENC
DEC
MAC
Crypto Officer
- PINs: W,E
- Secure
Channel
Session Keys:
E
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Unblock
PW1 -
OpenPGP
Reset user
PW1 using
reset-code or
PW3
return
code
0x9000
Reset code and
new PW1
success/error ENC
DEC
MAC
Crypto Officer
- PINs: W,E
- Secure
Channel
Session Keys:
E
Update
Reset-Code -
OpenPGP
Set or
update
resetting
code
return
code
0x9000
PW3 and reset
code
success/error ENC
DEC
MAC
Crypto Officer
- PINs: W,E
- Secure
Channel
Session Keys:
E
Validate -
OATH
Validate
Management
Auth Key
return
code
0x9000
host challenge
and response
mutual
authentication
response
ENC
DEC
MAC
RAND
Unauthenticat
ed
- OATH
Management
Auth Key: E
- Secure
Channel
Session Keys:
E
- DRBG State:
G,E
Verify PIN -
PIV
Verify user
PIN
return
code
0x9000
PIN success/error ENC
DEC
MAC
Unauthenticat
ed
- PINs: W,E
- Secure
Channel
Session Keys:
E
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Name Description Indicat
or
Inputs Outputs Security
Functio
ns
SSP Access
Verify PW1 -
OpenPGP
Verify using
user PIN
return
code
0x9000
PW1 success/error ENC
DEC
MAC
Unauthenticat
ed
- PINs: W,E
- Secure
Channel
Session Keys:
E
Verify PW3 -
OpenPGP
Verify using
admin PIN
return
code
0x9000
PW3 success/error ENC
DEC
MAC
Unauthenticat
ed
- PINs: W,E
- Secure
Channel
Session Keys:
E
Write Data -
OpenPGP
Write data
objects
except user
writable data
objects
return
code
0x9000
Data Object ID,
data
success/error ENC
DEC
MAC
Crypto Officer
- Secure
Channel
Session Keys:
E
Write Data
To
Containers -
PIV
Write any
container
return
code
0x9000
Container ID,
data
Success/error ENC
DEC
MAC
Crypto Officer
- Secure
Channel
Session Keys:
E
Write User
Protected
Data -
OpenPGP
Write user
writable data
objects
return
code
0x9000
Data Object ID,
data
success/error ENC
DEC
MAC
User
- Secure
Channel
Session Keys:
E
Table 15: Approved Services
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4.4 NON-APPROVED SERVICES
The module only supports non-Approved services within the OTP functional unit, which must be explicitly selected.
Name Description Algorithms Role
Write Config to Slot Write configuration and CSP in slot.
Zeroization.
None CO
Update Slot Configuration Update configuration (excluding key
material CSP) in slot
None CO
Emit Yubi-OTP from Slot Emit YubiOTP from slot AES (non-
compliant)
Unauthenticated
Emit HOTP from Slot Emit HOTP from slot HMAC (non-
compliant)
Unauthenticated
Emit Hash-OTP from Slot Emit HASH-OTP from slot HMAC (non-
compliant)
Unauthenticated
Perform Yubi-OTP
Challenge Response from
Slot
Perform YubiOTP challenge response with
AES 128 bit key stored in slot using user
supplied challenge
AES (non-
compliant)
Unauthenticated
Perform HMAC-SHA1
Challenge Response from
Slot
Compute SHA1 HMAC using 160 bits key
stored in slot using user supplied challenge
HMAC (non-
compliant)
Unauthenticated
Slot Device Serial Read serial from device None Unauthenticated
Slot YK Get Device Info Read device capabilities. None Unauthenticated
Slot YK Set Device Info Set device capabilities. None Unauthenticated
Write NDEF to Slot Write the NDEF URL and choose slot None CO
Table 16: Non-Approved Services
4.5 EXTERNAL SOFTWARE/FIRMWARE LOADED
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The module does not support external firmware loads.
5 SOFTWARE/FIRMWARE SECURITY
The hardware module contains executable firmware components and incorporates the following self-testing.
5.1 INTEGRITY TECHNIQUES
The module performs a 16-bit Error Detection Code for the Firmware Integrity Test, covering all executable codes.
5.2 INITIATE ON DEMAND
All self-tests may be invoked on demand by power cycling the module.
6 OPERATIONAL ENVIRONMENT
6.1 OPERATIONAL ENVIRONMENT TYPE AND REQUIREMENTS
Type of Operational Environment: Non-Modifiable
How Requirements are Satisfied:
The module is defined as a single-chip embodiment whose operational environment is classified as non-modifiable.
The firmware is loaded within manufacturing and then locked from being modified.
7 PHYSICAL SECURITY
7.1 MECHANISMS AND ACTIONS REQUIRED
The module is a single-chip embodiment with a hard, opaque enclosure. The IC packaging is tamper-evident and
removal-resistant.
Mechanism Inspection
Frequency
Inspection Guidance
IC packaging Monthly Inspect for physical evidence of tamper
Table 17: Mechanisms and Actions Required
7.2 EFP/EFT INFORMATION
The module does not support environmental failure protection (EFP) mechanisms for high/low voltage and
temperature extremes. The module underwent environmental failure testing (EFT) instead (refer to Table 18).
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Temp/Voltage
Type
Temperature
or Voltage
EFP
or
EFT
Result
LowTemperature -42C EFT Undefined Failure.
HighTemperature 128C EFT Undefined Failure.
LowVoltage 1.85v EFT The module shuts down.
HighVoltage 10.6v EFT Undefined Failure.
Table 18: EFP/EFT Information
7.3 HARDNESS TESTING TEMPERATURE RANGES
The module has been tested at the operational, storage and distribution temperatures listed in Table 19. The
module’s hardness is assured within these ranges.
Temperature
Type
Temperature
LowTemperature -25C
HighTemperature 85C
Table 19: Hardness Testing Temperatures
8 NON-INVASIVE SECURITY
8.1 MITIGATION TECHNIQUES
The module does not provide protections against non-invasive security methods.
9 SENSITIVE SECURITY PARAMETERS MANAGEMENT
9.1 STORAGE AREAS
All SSPs are stored in plaintext form within the volatile RAM or non-volatile flash memory.
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Storage
Area
Name
Description Persistence
Type
RAM Plaintext in volatile RAM Dynamic
NVM Plaintext in NVM Static
Table 20: Storage Areas
9.2 SSP INPUT-OUTPUT METHODS
Specific SSPs may be entered and output from the module via various methods including plaintext (direct entry), a
secure channel, and an Approved KTS.
Name From To Format
Type
Distribution
Type
Entry
Type
SFI or Algorithm
EE USB Host NVM Plaintext Manual Electronic
EO NVM or RAM USB Host Plaintext Manual Electronic
SCE USB or NFC Host NVM Encrypted Automated Electronic KTS-CBC-CMAC
SCO RAM USB or NFC Host Encrypted Automated Electronic KTS-CBC-CMAC
KTSE USB or NFC Host NVM or RAM Encrypted Automated Electronic AES-CCM (A5891)
KTSO NVM or RAM USB or NFC Host Encrypted Automated Electronic AES-CCM (A5891)
PP2E USB or NFC Host NVM Encrypted Automated Electronic KTS-CBC-HMAC
PP2O NVM or RAM USB or NFC Host Encrypted Automated Electronic KTS-CBC-HMAC
Table 21: SSP Input-Output Methods
9.3 SSP ZEROIZATION METHODS
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Each of the six functional units includes separate instructions for zeroization. In all cases, zeroization is the active
overwriting of SSP values with 0s.
Zeroization
Method
Description Rationale Operator Initiation
FIDO-Reset All CSPs zeroized with the CTAP
Offline Key and Wrapping Key
being re-generated.
SSPs are immediately
overwritten with 0s and the
CTAP Offline Key and
Wrapping Key are re-
generated.
Reset - FIDO service
OATH-Reset All CSPs zeroized SSPs are immediately
overwritten with 0s.
Reset - OATH service
OpenPGP-
Terminate
"TERMINATE APPLET" followed by
"ACTIVATE APPLET" services. All
CSPs zeroized with the PINs being
set to their default value.
CSPs are immediately
overwritten with 0s and then
reset to default values, as
applicable
Terminate Applet -
OpenPGP and
Activate Applet -
OpenPGP services.
PIV-Reset All CSPs zeroized with the PIV
Management Auth Key and PIN
being set to their default values.
SSPs are immediately
overwritten with 0s and then
reset to default values, as
applicable.
Reset - PIV service
SecureChannel-
Delete
CSPs zeroized. SSPs are immediately
overwritten with 0s.
Delete Key - SD
service
YubiHSM Auth-
Reset
All CSPs zeroized with PINs being
set to their default values.
SSPs are immediately
overwritten with 0s and PINs
being set to their default
values.
Reset - YubiHSM
Auth service
ZAU Ephemeral CSPs zeroised after use. SSPs are immediately
overwritten with 0s after use.
Automatic
ZPC Ephemeral CSPs zeroised upon
power cycle.
Ephemeral SSPs are
overwritten with 0s.
Power On service
Table 22: SSP Zeroization Methods
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9.4 SSPS
Name Description Size -
Strength
Type -
Category
Generated
By
Established
By
Used By
Asymmetric
Private Keys
Signature
generation and
RSA
unencapsulate for
PIV and OpenPGP
RSA 2048 -
4096;
ed255199; EC
P-256, P-384,
P-521, or
Non-NIST
Curve - 112 -
256
Private - CSP AKG SigGen
RSADP
RSASP
ECSP
Asymmetric
Public Keys
Used to verify
digital signatures
(external entities)
or perform RSA
Key Wrap
2048 - 4096;
256 - 521
(EC); 256
(EdDSA) -
112-256
Public - PSP AKG SigVer
Attestation Key Attest internally
generated
asymmetric keys
112-256 -
112-256
Private -
Neither
Pre-loaded SigGen
CTAP Offline
Key
To support the
HMAC-Secret
FIDO extension
112 - 112 MAC - CSP SymKG MAC
CTAP PIN token Used as part of
FIDO2
authentication
112 - 112 MAC - CSP RAND MAC
CTAP Session
Keys
Secure Session 256, 112 -
256, 112
Symmetric,
MAC - CSP
KAS-PP2 ENC
DEC
MAC
KTS-
CBC-
HMAC
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Name Description Size -
Strength
Type -
Category
Generated
By
Established
By
Used By
DRBG Seed Seeds the DRBG.
Personalization
string is 384 bits.
1600 bits -
384
ENT - CSP ESV Counter
DRBG
(A5891)
DRBG State Random number
generation. V and
Key
V = 128, Key =
256 - 256 bit
ENT - CSP Counter
DRBG
(A5891)
RAND
SymKG
AKG
Entropy Input Entropy for the
DRBG
1216 bits -
384 (3/2
security
strength)
ENT - CSP ESV Counter
DRBG
(A5891)
KAS Private
Keys
Key
establishment
EC P-256, P-
384, P-521, or
Non-NIST
Curve - 128 -
256
Private - CSP KAS-KG KAS-PP2
KAS-
SCP11
SSC
KAS Public Keys Key
establishment
public keys.
128-bit
minimum -
128-bit
minimum
Public - PSP KAS-KG KAS-PP2
KAS-
SCP11
SSC
OATH
Management
Auth Key
OATH
authentication
secret
112 - 112 MAC - CSP Configured
by operator
MAC
OATH Seed Key Used to generate
HOTPs or TOTPs
112 - 112 MAC - CSP MAC
PINs Authenticate
operators
Minimum 48-
bits - NA
Authentication
- CSP
Pre-loaded
or
configured
by operator
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Name Description Size -
Strength
Type -
Category
Generated
By
Established
By
Used By
PIV
Management
Auth Key
PIV
authentication
secret
128 - 256 -
128
Symmetric -
CSP
Pre-loaded ENC
DEC
Secure Channel
Authentication
Keys
Used to derive
session keys for
Secure Channel
(SCP03 or
YubiHSM Auth)
128 - 128 Symmetric -
CSP
Default set
is pre-
loaded
KBKDF
Secure Channel
Sensitive Data
Key
Used for Sensitive
Data Decryption
128 - 128 Symmetric -
CSP
Default set
is pre-
loaded
ENC
DEC
Secure Channel
Session Keys
Secure sessions
(SCP03, SCP11,
YubiHSM Auth)
128 - 128 Symmetric -
CSP
KBKDF
KAS-SCP11
ENC
DEC
MAC
KTS-
CBC-
CMAC
Shared Secret Output from ECC
CDH
256-521 -
128-256
Shared Secret -
CSP
SSC SSC
Wrapping Key Used to wrap
FIDO keys
256 - 256 Symmetric -
CSP
SymKG KTS-
CCM
Table 23: SSP Table 1
Name Input -
Output
Storage Storage
Duration
Zeroization Related SSPs
Asymmetric Private
Keys
EE
SCE
SCO
RAM:Plaintext
NVM:Plaintext
Until Use PIV-Reset
OpenPGP-
Terminate
FIDO-Reset
DRBG State:Derived From
Asymmetric Public
Keys:Used With
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Name Input -
Output
Storage Storage
Duration
Zeroization Related SSPs
KTSE
KTSO
SecureChannel-
Delete
Asymmetric Public
Keys
EE
SCE
KTSE
EO
SCO
KTSO
NVM:Plaintext Until Use PIV-Reset
OpenPGP-
Terminate
FIDO-Reset
SecureChannel-
Delete
DRBG State:Derived From
Attestation Key EE
SCE
NVM:Plaintext Until Use N/A Secure Channel Session
Keys:Used With
CTAP Offline Key NVM:Plaintext Until Use FIDO-Reset DRBG State:Derived From
CTAP PIN token EO
SCO
PP2O
RAM:Plaintext Until Use ZPC DRBG State:Used With
CTAP Session Keys:Used
With
CTAP Session Keys RAM:Plaintext Until Use ZAU PINs:Used With
CTAP PIN token:Used With
DRBG Seed RAM:Plaintext Until use ZAU DRBG State:Used With
Entropy Input:Used With
DRBG State RAM:Plaintext Until
reboot
ZPC DRBG Seed :Used With
Entropy Input RAM:Plaintext Until use ZAU DRBG Seed:Used With
KAS Private Keys EE
SCE
NVM:Plaintext
RAM:Plaintext
Until Use PIV-Reset
OpenPGP-
Terminate
FIDO-Reset
YubiHSM Auth-
Reset
DRBG State:Derived From
KAS Public Keys:Used With
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Name Input -
Output
Storage Storage
Duration
Zeroization Related SSPs
SecureChannel-
Delete
KAS Public Keys EE
SCE
EO
SCO
RAM:Plaintext
NVM:Plaintext
Until Use PIV-Reset
OpenPGP-
Terminate
FIDO-Reset
YubiHSM Auth-
Reset
SecureChannel-
Delete
DRBG State:Derived From
Secure Channel Session
Keys:Used With
KAS Public Keys:Paired
With
OATH Management
Auth Key
EE
SCE
NVM:Plaintext Until Use OATH-Reset Secure Channel Session
Keys:Used With
OATH Seed Key EE
SCE
NVM:Plaintext Until Use OATH-Reset Secure Channel Session
Keys:Used With
PINs EE
SCE
PP2E
NVM:Plaintext Until Use PIV-Reset
OpenPGP-
Terminate
FIDO-Reset
YubiHSM Auth-
Reset
Secure Channel Session
Keys:Used With
CTAP Session Keys:Used
With
PIV Management
Auth Key
EE
SCE
NVM:Plaintext Until Use PIV-Reset Secure Channel Session
Keys:Used With
Secure Channel
Authentication Keys
EE
SCE
NVM:Plaintext Until use YubiHSM Auth-
Reset
SecureChannel-
Delete
Secure Channel Session
Keys:Used With
Secure Channel
Sensitive Data Key
EE
SCE
NVM:Plaintext
RAM:Plaintext
Until use SecureChannel-
Delete
Secure Channel
Authentication Keys:Used
With
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Name Input -
Output
Storage Storage
Duration
Zeroization Related SSPs
KAS Private Keys:Used
With
Secure Channel
Session Keys
EO
SCO
RAM:Plaintext Until Use ZAU Secure Channel
Authentication
Keys:Derived From
Secure Channel Sensitive
Data Key:Used With
PINs:Used With
PIV Management Auth
Key:Used With
OATH Management Auth
Key:Used With
OATH Seed Key:Used With
Asymmetric Private
Keys:Used With
KAS Private Keys:Used
With
KAS Public Keys:Used With
Shared Secret EO
SCO
RAM:Plaintext Until Use PIV-Reset
OATH-Reset
OpenPGP-
Terminate
FIDO-Reset
YubiHSM Auth-
Reset
SecureChannel-
Delete
KAS Private Keys:Used
With
KAS Public Keys:Used With
Wrapping Key NVM:Plaintext Until Use FIDO-Reset DRBG State:Derived From
Asymmetric Private
Keys:Used With
Table 24: SSP Table 2
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10 SELF-TESTS
The following pre-operational and conditional self-tests are performed by the module. All self-tests are performed
regardless of whether the module currently offers non-approved services, that is, whether OTP is selected (NFC) or
the designated OTP endpoints are used. The data output interface is inhibited whenever the cryptographic module
is in a self-test condition.
10.1 PRE-OPERATIONAL SELF-TESTS
The following pre-operational test is performed upon power-up and on-demand, the latter by power-cycling the
module.
Algorithm
or Test
Test Properties Test
Method
Test Type Indicator Details
LRC 16-bit Error Detection Code KAT SW/FW Integrity Implicit N/A
Table 25: Pre-Operational Self-Tests
10.2 CONDITIONAL SELF-TESTS
The following conditional tests are performed upon power-up, on-demand and periodically.
Algorithm or
Test
Test Properties Test Method Test
Type
Indicator Details Conditions
AES-CCM
(A5891)
128-bit KAT CAST Implicit Encrypt Power-On
AES-ECB
(A5891)
128-bit KAT CAST Implicit Decrypt Power-On
Counter DRBG
(A5891)
CTR_DRBG KAT CAST Implicit SP800-90A Health
Tests for Instantiate,
Reseed, and Generate
Power-On
ECDSA SigGen
(FIPS186-5)
(A5891)
P-256, SHA2-
256
KAT CAST Implicit Sign Before first
use
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Algorithm or
Test
Test Properties Test Method Test
Type
Indicator Details Conditions
ECDSA SigVer
(FIPS186-5)
(A5891)
P-256, SHA2-
256
KAT CAST Implicit Verify Before first
use
EDDSA SigGen
(A5891)
Ed25519,
SHA2-512
KAT CAST Implicit Sign Before first
use
EDDSA SigVer
(A5891)
Ed25519,
SHA2-512
KAT CAST Implicit Verify Before first
use
KAS-ECC-SSC
Sp800-56Ar3
(A5891)
P-256 KAT CAST Implicit SSC Before first
use
KDA HKDF
SP800-56Cr2
(A5891)
HMAC-SHA2-
256
KAT CAST Implicit Key Derivation Power-On
KDF ANS 9.63
(A5891)
X9.63 KAT CAST Implicit Key Derivation Power-On
KDF SP800-108
(A5891)
AES CMAC KAT CAST Implicit Key Derivation Power-On
PWCT Sign/Verify Sign/Verify PCT Implicit EC, ED, RSA Upon Key
Generation
RSA SigGen
(FIPS186-5)
(A5891)
2048-bit
PKCS#1 with
SHA2-256
KAT CAST Implicit Sign Before first
use
RSA SigVer
(FIPS186-5)
(A5891)
2048-bit
PKCS#1 with
SHA2-256
KAT CAST Implicit Verify Before first
use
SHS (A5891) SHA-1, SHA2-
512
KAT CAST Implicit Hash Power-On
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Algorithm or
Test
Test Properties Test Method Test
Type
Indicator Details Conditions
SP800-90B APT, RCT SP800-90B
Health Tests
CAST Implicit APT, RCT Upon use
Table 26: Conditional Self-Tests
10.3 PERIODIC SELF-TEST INFORMATION
The module will perform periodic self-tests every 29 hours.
Algorithm or Test Test Method Test Type Period Periodic Method
LRC KAT SW/FW Integrity 29 hours Automatic
Table 27: Pre-Operational Periodic Information
Algorithm or Test Test Method Test Type Period Periodic Method
AES-CCM (A5891) KAT CAST Power-On Manual
AES-ECB (A5891) KAT CAST Power-On Manual
Counter DRBG
(A5891)
KAT CAST Power-On Manual
ECDSA SigGen
(FIPS186-5) (A5891)
KAT CAST Power-On Manual
ECDSA SigVer
(FIPS186-5) (A5891)
KAT CAST Power-On Manual
EDDSA SigGen
(A5891)
KAT CAST Power-On Manual
EDDSA SigVer
(A5891)
KAT CAST Power-On Manual
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Algorithm or Test Test Method Test Type Period Periodic Method
KAS-ECC-SSC Sp800-
56Ar3 (A5891)
KAT CAST Power-On Manual
KDA HKDF SP800-
56Cr2 (A5891)
KAT CAST Power-On Manual
KDF ANS 9.63
(A5891)
KAT CAST Power-On Manual
KDF SP800-108
(A5891)
KAT CAST Power-On Manual
PWCT Sign/Verify PCT Power-On Manual
RSA SigGen
(FIPS186-5) (A5891)
KAT CAST Power-On Manual
RSA SigVer
(FIPS186-5) (A5891)
KAT CAST Power-On Manual
SHS (A5891) KAT CAST Power-On Manual
SP800-90B SP800-90B Health
Tests
CAST 29 hours Automatic
Table 28: Conditional Periodic Information
10.4 ERROR STATES
The module transitions into the error state when an error condition is encountered and provides an error status
indicator (i.e., blinking an attached LED before rebooting). All data output and cryptographic functions are
inhibited while the module is in the error state (refer to Table 29).
Name Description Conditions Recovery
Method
Indicator
Error
State
Upon detection of any failures in a pre-
operational or conditional self-test
Self-test
failure
Power
Cycle
Attached LED blinks special
sequence, then reboots.
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Table 29: Error States
10.5 OPERATOR INITIATION OF SELF-TESTS
Self-tests may be invoked on demand by power cycling the module or invoking a soft reset through the services.
11 LIFE-CYCLE ASSURANCE
There are no specific maintenance requirements.
11.1 INSTALLATION, INITIALIZATION, AND STARTUP PROCEDURES
The module powers up in an uninitialized state. The following initialization procedures for each functional unit
must be adhered to prior to first use. Only when this procedure is completed will the module operate in the
Approved mode. The only non-Approved services are contained by the OTP functional unit. In order to access the
OTP functional unit, OTP must be selected (NFC) or the designated OTP endpoints must be used (USB). (See
Section 2.4). While OTP is selected, no other services beyond OTP services, namely those listed in Section 4.4, are
available. The module enters the non-Approved mode whenever a non-Approved service is invoked and exits when
the said service completes.
PIV, OpenPGP, OATH, FIDO, Security Domain (SD) and HSMAuth functional units must be initialized to be utilized in
the Approved mode. The following describes the details in this regard for the individual functional units.
Command-line and GUI-based instructions to be performed by the Crypto Officer or the User of the module can be
found in the FIPS 140-3 Configuration section of the YubiKey Technical Manual.
− PIV:
o Update the values for the PIV Management Auth Key, PIN and PUK the default values of which
are 010203040506070801020304050607080102030405060708, 123456, and 12345678,
respectively.
o The values of the PIV Management Auth Key and the PUK are to be updated by the Crypto
Officer. The value of the PIN is to be updated by the User.
− OpenPGP:
o Update the default User PIN (PW1) and Admin PIN (PW3) the default values of which are 123456
and 12345678, respectively.
o The value of the Admin PIN is to be updated by the Crypto Officer while the value of the User PIN
is to be updated by the User.
− OATH:
o Set an OATH Management Auth Key, which has no default value.
o The value of the OATH Management Auth Key is to be set by the Crypto Officer.
− FIDO:
o Set a PIN which has no default value.
o The value of the PIN is to be set by the User.
− YubiHSM Auth:
o Set the Admin PIN, which has no default value.
o The value of the Admin PIN is to be set by the Crypto Officer.
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− Security Domain:
o Update the default key set the default values of which are
404142434445464748494a4b4c4d4e4f for all three keys.
o The values of the keys in the key set are to be updated by the Crypto Officer.
11.2 ADMINISTRATOR GUIDANCE
There are no further instructions for administrators beyond those outlined in the Installation, Initialization, and
Startup Procedures.
11.3 NON-ADMINISTRATOR GUIDANCE
There are no further instructions for non-administrators beyond those outlined in the Installation, Initialization,
and Startup Procedures
11.4 DESIGN AND RULES
The following security rules are enforced by the cryptographic module to ensure the FIPS 140-3 security
requirements are met.
1. The module supports an Approved and non-Approved mode of operation. The Approved mode indicator
must be returned to the end user.
2. The module does not allow unauthenticated operators to have any access to the module’s cryptographic
services.
3. The module inhibits data output during self-tests, firmware load, zeroization and error states.
4. The module logically separates data output from the processes performing zeroization and key
generation.
5. The module enforces role-based authentication.
6. The module does not retain the authentication of an operator following power-off or reboot.
7. The module supports the following roles: Cryptographic Officer and User.
8. The module does not support a bypass mode or maintenance mode.
9. The module supports the following logically distinct interfaces:
− Data input interface
− Data output interface
− Control input interface
− Status output interface
− Power interface
10. The module protects critical security parameters from unauthorized disclosure, modification and
substitution.
11. The module performs power-on, on-demand and periodic self-testing.
12. The module logs errors whenever an error state is entered.
13. The module does not perform any cryptographic functions while in an error state.
14. The module does not support multiple concurrent operators.
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11.5 END OF LIFE
Zeroize the module and dispose of it at a proper e-waste facility.
12 MITIGATION OF OTHER ATTACKS
The module is not purposefully designed to mitigate any attacks beyond the scope of FIPS 140-3 requirements.
13 REFERENCES
YubiKey Technical Manual, March 2026, https://docs.yubico.com/hardware/yubikey/yk-tech-manual/fips-140-3-
nist-requirement.html