National Information Assurance Partnership
Common Criteria Evaluation and Validation Scheme
Validation Report
Extreme Networks, Inc. SLX Product Series operating
with Version 20.2.1aa
Report Number: CCEVS-VR-11198-2021
Dated: July 22, 2021
Version: 1.0
National Institute of Standards and Technology Department of Defense
Information Technology Laboratory ATTN: NIAP, SUITE: 6982
100 Bureau Drive 9800 Savage Road
Gaithersburg, MD 20899 Fort George G. Meade, MD 20755-6982
®
TM
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ACKNOWLEDGEMENTS
Validation Team
Jenn Dotson
Lisa Mitchell
Clare Parran
Chris Thorpe
The MITRE Corporation
Common Criteria Testing Laboratory
Justin Bettencourt
Cornelius Haley
Gossamer Security Solutions, Inc.
Columbia, MD
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Table of Contents
1 Executive Summary.................................................................................................... 1
2 Identification............................................................................................................... 1
3 Architectural Information ........................................................................................... 3
3.1 TOE Evaluated Platforms ................................................................................... 3
3.2 TOE Architecture................................................................................................ 3
3.3 Physical Boundaries............................................................................................ 4
4 Security Policy............................................................................................................ 4
4.1 Security audit ...................................................................................................... 4
4.2 Cryptographic support ........................................................................................ 4
4.3 Identification and authentication......................................................................... 5
4.4 Security management.......................................................................................... 5
4.5 Protection of the TSF.......................................................................................... 5
4.6 TOE access.......................................................................................................... 5
4.7 Trusted path/channels ......................................................................................... 5
5 Assumptions................................................................................................................ 6
6 Clarification of Scope ................................................................................................. 6
7 Documentation............................................................................................................ 6
8 IT Product Testing ...................................................................................................... 7
8.1 Developer Testing............................................................................................... 7
8.2 Evaluation Team Independent Testing ............................................................... 7
9 Results of the Evaluation ............................................................................................ 7
9.1 Evaluation of the Security Target (ASE)............................................................ 7
9.2 Evaluation of the Development (ADV) .............................................................. 7
9.3 Evaluation of the Guidance Documents (AGD) ................................................. 8
9.4 Evaluation of the Life Cycle Support Activities (ALC)..................................... 8
9.5 Evaluation of the Test Documentation and the Test Activity (ATE) ................. 8
9.6 Vulnerability Assessment Activity (VAN)......................................................... 9
9.7 Summary of Evaluation Results.......................................................................... 9
10 Validator Comments/Recommendations .................................................................. 10
11 Annexes..................................................................................................................... 10
12 Security Target.......................................................................................................... 10
13 Glossary .................................................................................................................... 10
14 Bibliography ............................................................................................................. 11
1
1 Executive Summary
This report documents the assessment of the National Information Assurance Partnership
(NIAP) Validation team of the evaluation of Extreme Networks, Inc. SLX Product Series
operating with Version 20.2.1aa provided by Extreme Networks, Inc. It presents the
evaluation results, their justifications, and the conformance results. This Validation Report
(VR) is not an endorsement of the Target of Evaluation (TOE) by any agency of the U.S.
government, and no warranty is either expressed or implied.
The evaluation was performed by the Gossamer Security Solutions (Gossamer) Common
Criteria Testing Laboratory (CCTL) in Columbia, MD, United States of America, and was
completed in July 2021. The information in this report is largely derived from the
Evaluation Technical Report (ETR) and associated test reports, all written by Gossamer
Security Solutions. The evaluation determined that the product is both Common Criteria
Part 2 Extended and Part 3 Conformant and meets the assurance requirements of the
collaborative Protection Profile for Network Devices, version 2.2e Version 2.2e, 23 March
2020.
The Target of Evaluation (TOE) is the Extreme Networks, Inc. SLX Product Series
operating with Version 20.2.1aa family of products.
The TOE identified in this VR has been evaluated at a NIAP approved CCTL using the
Common Methodology for IT Security Evaluation (Version 3.1, Rev 5) for conformance
to the Common Criteria for IT Security Evaluation (Version 3.1, Rev 5). This Validation
Report applies only to the specific version of the TOE as evaluated. The evaluation has
been conducted in accordance with the provisions of the NIAP Common Criteria
Evaluation and Validation Scheme (CCEVS) and the conclusions of the testing laboratory
in the evaluation technical report are consistent with the evidence provided.
The Validation team monitored the activities of the Evaluation team, provided guidance on
technical issues and evaluation processes, and reviewed the individual work units and
successive versions of the ETR. The Validation team found that the evaluation showed that
the product satisfies all of the functional requirements and assurance requirements stated
in the Security Target (ST). Therefore, the Validation team concludes that the testing
laboratory’s findings are accurate, the conclusions justified, and the conformance results
are correct. The conclusions of the testing laboratory in the ETR are consistent with the
evidence produced.
The technical information included in this report was obtained from the Extreme Networks,
Inc. SLX Product Series operating with Version 20.2.1aa Security Target, Version 0.6, July
19, 2021 and analysis performed by the Validation Team.
2 Identification
The CCEVS is a joint National Security Agency (NSA) and National Institute of Standards
and Technology (NIST) effort to establish commercial facilities to perform trusted product
evaluations. Under this program, security evaluations are conducted by commercial testing
laboratories called Common Criteria Testing Laboratories (CCTLs) using the Common
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Evaluation Methodology (CEM) in accordance with National Voluntary Laboratory
Assessment Program (NVLAP) accreditation.
The NIAP Validation Body assigns Validators to monitor the CCTLs to ensure quality and
consistency across evaluations. Developers of information technology products desiring a
security evaluation contract with a CCTL and pay a fee for their product’s evaluation.
Upon successful completion of the evaluation, the product is added to NIAP’s Validated
Products List.
Table 1 provides information needed to completely identify the product, including:
• The TOE: the fully qualified identifier of the product as evaluated.
• The ST, describing the security features, claims, and assurances of the product.
• The conformance result of the evaluation.
• The Protection Profile (PP) to which the product is conformant.
• The organizations and individuals participating in the evaluation.
Table 1: Evaluation Identifiers
Item Identifier
Evaluation Scheme United States NIAP Common Criteria Evaluation and Validation Scheme
TOE Extreme Networks, Inc. SLX Product Series operating with Version 20.2.1aa
(Specific models identified in Section 3.1)
Protection Profile collaborative Protection Profile for Network Devices, Version 2.2e, 23 March
2020 (NDcPP22e)
ST Extreme Networks, Inc. SLX Product Series operating with Version 20.2.1aa
Security Target, Version 0.6, July 19, 2021
Evaluation Technical
Report
Evaluation Technical Report for Extreme Networks, Inc. SLX Product Series
operating with Version 20.2.1aa, ETR Version 0.4, July 19, 2021
CC Version Common Criteria for Information Technology Security Evaluation, Version 3.1,
rev 5
Conformance Result CC Part 2 extended, CC Part 3 conformant
Sponsor Extreme Networks, Inc.
Developer Extreme Networks, Inc.
Common Criteria
Testing Lab (CCTL)
Gossamer Security Solutions, Inc.
CCEVS Validators Jenn Dotson, Lisa Mitchell, Clare Parran, Chris Thorpe
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3 Architectural Information
Note: The following architectural description is based on the description presented in the
ST.
The TOE is the SLX Product Series operating with Version 20.2.1aa. The SLX Product
Series operating with Version 20.2.1aa are hardware appliances with embedded software
installed on a management processor. The embedded software is a version of Extreme
Network’s proprietary Operating System (OS). The OS controls the switching and routing
of network frames and packets among the connections available on the hardware
appliances.
3.1 TOE Evaluated Platforms
The TOE is the SLX Product Series operating with Version 20.2.1aa including the models
shown in Table 3-1.
While there are different models in the SLX Product Series, they differ primarily in
physical form factor, number and types of connections and slots, and relative performance.
While there are some functional differences among the models, they each provide the same
security characteristics as claimed in the ST.
Model CPU
SLX 9540
Intel Broadwell processor
Intel(R) Xeon(R) CPU 1527
SLX 9740
Intel Denverton processor
Intel(R) Atom(TM) CPU C3758
Table 3-1 Evaluated Models & Processors
3.2 TOE Architecture
The basic architecture of each TOE appliance begins with a hardware appliance with
physical network connections. Within the hardware appliance, the TOE is designed to
control and enable access to the available hardware functions (e.g., program execution,
device access, facilitate basic routing and switching functions).
All TOE appliances are configured at the factory with default parameters and an admin and
user account with default passwords. Users must login to access the system’s basic features
through its Command Line Interface (CLI). However, the product should be configured in
accordance with the evaluated configuration prior to being placed into operation. The CLI
is a text based interface which is accessible from a directly connected terminal or via a
remote terminal using SSH. Administrators can also use REST APIs (over HTTPS) or
NetConf (over SSH) for configuring the TOE. The TOE uses SCP to download/compare
software images. All of the remote management interfaces are protected using encryption
as explained in the ST.
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3.3 Physical Boundaries
Each TOE appliance runs a version of the Extreme proprietary OS and has physical
network connections to its environment to facilitate routing and switching of network
traffic. The TOE appliance can also be the destination of network traffic, where it provides
interfaces for its own management.
The TOE may be accessed and managed through a PC or terminal in the environment which
can be remote from or directly connected to the TOE.
The TOE can be configured to forward its audit records to a syslog server in the
environment. This is generally advisable given the limited audit log storage space on the
evaluated appliances.
The TOE sets its internal clock using administrative commands issued at the CLI interface
or can use a Network Time Protocol (NTP) server.
The evaluation includes an audit server, management workstation, NTP server and
certificate authority in the IT environment. The scope of the evaluation is limited to the
requirements in the ST – all other functionality is outside the scope of the evaluation.
4 Security Policy
This section summaries the security functionality of the TOE:
1. Security audit
2. Cryptographic support
3. Identification and authentication
4. Security management
5. Protection of the TSF
6. TOE access
7. Trusted path/channels
4.1 Security audit
The TOE generates audit events for numerous activities including policy enforcement,
system management and authentication. A syslog server in the environment is relied on to
store audit records generated by the TOE. The TOE generates a complete audit record
including the IP address of the TOE, the event details, and the time the event occurred.
The time stamp is provided by the TOE appliance hardware.
4.2 Cryptographic support
The TOE contains CAVP-tested cryptographic implementations that provide key
management, random bit generation, encryption/decryption, digital signature and secure
hashing and key-hashing features in support of higher-level cryptographic protocols
including SSH and TLS.
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4.3 Identification and authentication
The TOE authenticates administrative users. In order for an administrative user to access
the TOE, a user account including a user name and password must be created for the user,
and an administrative role must be assigned. The TOE performs the validation of the login
credentials and also supports use of a RADIUS server.
4.4 Security management
The TOE provides Command Line Interface (CLI) commands to access the wide range of
security management functions to manage its security policies. The TOE also provides
REST APIs (protected by TLS) and NetConf (protected by SSH) to configure the TOE.
Security management commands are limited to authorized users (i.e., administrators) and
available only after they have provided acceptable user identification and authentication
data to the TOE. Only the Authorized Administrator role can actually manage the security
policies provided by the TOE and the TOE offers a complete set of functions to facilitate
effective management.
4.5 Protection of the TSF
The TOE implements a number of features design to protect itself to ensure the reliability
and integrity of its security features.
It protects particularly sensitive data such as stored passwords and cryptographic keys so
that they are not accessible even by an administrator. It also provides its own timing
mechanism to ensure that reliable time information is available (e.g., for log
accountability).
The TOE includes functions to perform self-tests so that it might detect when it is failing.
It also includes mechanisms (i.e., verification of the digital signature of each new image)
so that the TOE itself can be updated while ensuring that the updates will not introduce
malicious or other unexpected changes in the TOE.
4.6 TOE access
The TOE can be configured to display a message of the day banner when an administrator
establishes an interactive session and subsequently will enforce an administrator-defined
inactivity timeout value after which the inactive session (local or remote) will be
terminated.
4.7 Trusted path/channels
The TOE protects interactive communication with administrators using SSHv2 for CLI and
NetConf access, ensuring both integrity and disclosure protection. If the negotiation of an
encrypted session fails or if the user does not have authorization for remote administration,
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an attempted connection will not be established. The TOE also provides a REST API
interface for security management that is protected with TLS.
The TOE protects communication with network peers, such as a log server and RADIUS
Server, using TLS connections to prevent unintended disclosure or modification of logs.
SSHv2 is used to support SCP which the TOE uses for download of TOE updates.
5 Assumptions
The Security Problem Definition, including the assumptions, may be found in the following
documents:
• collaborative Protection Profile for Network Devices, Version 2.2e, 23 March 2020
That information has not been reproduced here and the NDcPP22e should be consulted if
there is interest in that material.
6 Clarification of Scope
The scope of this evaluation was limited to the functionality and assurances covered in the
NDcPP22e and applicable Technical Decisions as described for this TOE in the ST. Other
functionality included in the product was not assessed as part of this evaluation. All other
functionality provided by the devices needs to be assessed separately, and no further
conclusions can be drawn about their effectiveness.
All evaluations (and all products) have limitations, as well as potential misconceptions that
need clarification. This text covers some of the more important limitations and
clarifications of this evaluation. Note that:
• As with any evaluation, this evaluation only shows that the evaluated configuration
meets the security claims made with a certain level of assurance (the assurance
activities specified in the collaborative Protection Profile for Network Devices and
performed by the Evaluation team).
• This evaluation covers only the specific device models and software as identified
in this document, and not any earlier or later versions released or in process.
• This evaluation did not specifically search for, nor attempt to exploit, vulnerabilities
that were not “obvious” or vulnerabilities to objectives not claimed in the ST. The
CEM defines an “obvious” vulnerability as one that is easily exploited with a
minimum of understanding of the TOE, technical sophistication and resources.
7 Documentation
The following documents were available with the TOE for evaluation:
• Extreme SLX-OS Common Criteria Configuration Guide, 20.2.1aa, Version 2.5.2,
7 July 2021
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8 IT Product Testing
This section describes the testing efforts of the developer and the Evaluation Team. It is
derived from information contained in the Detailed Test Report for Extreme Networks, Inc.
SLX Product Series operating with Version 20.2.1aa, Version 0.4, July 19, 2021 (DTR).
8.1 Developer Testing
No evidence of developer testing is required in the assurance activities for this product.
8.2 Evaluation Team Independent Testing
The Evaluation team verified the product according a Common Criteria Certification
document and ran the tests specified in the NDcPP22e including the tests associated with
optional requirements. Test activities were conducted at the Gossamer Security Solutions
test facility in Columbia, Maryland between November 2020 and April of 2021.
9 Results of the Evaluation
The results of the assurance requirements are generally described in this section and are
presented in detail in the proprietary ETR. The reader of this document can assume that all
assurance activities and work units received a passing verdict.
A verdict for an assurance component is determined by the resulting verdicts assigned to
the corresponding evaluator action elements. The evaluation was conducted based upon
CC version 3.1 rev 5 and CEM version 3.1 rev 5. The evaluation determined the Extreme
Networks, Inc. SLX Product Series operating with Version 20.2.1aa TOE to be Part 2
extended, and to meet the SARs contained in the NDcPP22e.
9.1 Evaluation of the Security Target (ASE)
The Evaluation team applied each ASE CEM work unit. The ST evaluation ensured the
ST contains a description of the environment in terms of policies and assumptions, a
statement of security requirements claimed to be met by the Extreme Networks, Inc. SLX
Product Series operating with Version 20.2.1aa products that are consistent with the
Common Criteria, and product security function descriptions that support the requirements.
The Validation team reviewed the work of the Evaluation team and found that sufficient
evidence and justification was provided by the Evaluation team to confirm that the
evaluation was conducted in accordance with the requirements of the CEM, and that the
conclusion reached by the Evaluation team was justified.
9.2 Evaluation of the Development (ADV)
The Evaluation team applied each ADV CEM work unit. The Evaluation team assessed the
design documentation and found it adequate to aid in understanding how the TSF provides
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the security functions. The design documentation consists of a functional specification
contained in the Security Target and Guidance document. Additionally, the Evaluation
team performed the assurance activities specified in the NDcPP22e related to the
examination of the information contained in the TSS.
The Validation team reviewed the work of the Evaluation team and found that sufficient
evidence and justification was provided by the Evaluation team to confirm that the
evaluation was conducted in accordance with the requirements of the CEM, and that the
conclusion reached by the Evaluation team was justified.
9.3 Evaluation of the Guidance Documents (AGD)
The Evaluation team applied each AGD CEM work unit. The Evaluation team ensured the
adequacy of the user guidance in describing how to use the operational TOE. Additionally,
the Evaluation team ensured the adequacy of the administrator guidance in describing how
to securely administer the TOE. The guidance was assessed during the design and testing
phases of the evaluation to ensure it was complete.
The Validation team reviewed the work of the Evaluation team and found that sufficient
evidence and justification was provided by the Evaluation team to confirm that the
evaluation was conducted in accordance with the requirements of the CEM, and that the
conclusion reached by the Evaluation team was justified.
9.4 Evaluation of the Life Cycle Support Activities (ALC)
The Evaluation team applied each ALC CEM work unit. The Evaluation team found that
the TOE was identified.
The Validation team reviewed the work of the Evaluation team and found that sufficient
evidence and justification was provided by the Evaluation team to confirm that the
evaluation was conducted in accordance with the requirements of the CEM, and that the
conclusion reached by the Evaluation team was justified.
9.5 Evaluation of the Test Documentation and the Test Activity (ATE)
The Evaluation team applied each ATE CEM work unit. The Evaluation team ran the set
of tests specified by the assurance activities in the NDcPP22e and recorded the results in a
Test Report, summarized in the AAR.
The Validation team reviewed the work of the Evaluation team and found that sufficient
evidence and justification was provided by the Evaluation team to confirm that the
evaluation was conducted in accordance with the requirements of the CEM, and that the
conclusion reached by the Evaluation team was justified.
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9.6 Vulnerability Assessment Activity (VAN)
The Evaluation team applied each AVA CEM work unit. The vulnerability analysis is in
the DTR prepared by the evaluator. The vulnerability analysis includes a public search
for vulnerabilities. The public search for vulnerabilities did not uncover any residual
vulnerability.
The evaluation team performed a public search for vulnerabilities on July 19, 2021 and did
not discover any public issues with the TOE. The terms used for the search were as follows:
• “Extreme”,
• “SLX”,
• “openssl”,
• “openssh”,
• “EXTR-SLX-CRYPTO-VER-1.0”,
• “Xeon processor”, and
• “Atom processor”.
Using the following resources:
• National Vulnerability Database (https://web.nvd.nist.gov/vuln/search),
• Vulnerability Notes Database (http://www.kb.cert.org/vuls/),
• Rapid7 Vulnerability Database (https://www.rapid7.com/db/vulnerabilities),
• Tipping Point Zero Day Initiative
(http://www.zerodayinitiative.com/advisories ),
• Exploit / Vulnerability Search Engine (http://www.exploitsearch.net),
• SecurITeam Exploit Search (http://www.securiteam.com),
• Tenable Network Security (http://nessus.org/plugins/index.php?view=search),
• Offensive Security Exploit Database (https://www.exploit-db.com/)
The Validation team reviewed the work of the Evaluation team and found that sufficient
evidence and justification was provided by the Evaluation team to confirm that the
evaluation was conducted in accordance with the requirements of the CEM, and that the
conclusion reached by the Evaluation team was justified.
9.7 Summary of Evaluation Results
The Evaluation team’s assessment of the evaluation evidence demonstrates that the claims
in the ST are met. Additionally, the Evaluation team’s testing also demonstrated the
accuracy of the claims in the ST.
The Validation team’s assessment of the evidence provided by the Evaluation team is that
it demonstrates that the Evaluation team followed the procedures defined in the CEM, and
correctly verified that the product meets the claims in the ST.
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10 Validator Comments/Recommendations
The Validation team suggest that the consumer pay particular attention to the evaluated
configuration of the TOE. As stated in the Clarification of Scope, the evaluated
functionality is scoped exclusively to the security functional requirements specified in the
ST, and the only evaluated functionality was that which was described by the SFRs claimed
in the ST. All other functionality provided by the TOE needs to be assessed separately and
no further conclusions can be drawn about its effectiveness.
Consumers employing the TOE must follow the configuration instructions provided in the
Configuration Guidance documentation listed in Section 7 to ensure the evaluated
configuration is established and maintained.
11 Annexes
Not applicable
12 Security Target
Extreme Networks, Inc. SLX Product Series operating with Version 20.2.1aa Security
Target, Version 0.6, July 19, 2021
13 Glossary
The following definitions are used throughout this document:
• Common Criteria Testing Laboratory (CCTL). An IT security evaluation facility
accredited by the National Voluntary Laboratory Accreditation Program (NVLAP) and
approved by the CCEVS Validation Body to conduct Common Criteria-based
evaluations.
• Conformance. The ability to demonstrate in an unambiguous way that a given
implementation is correct with respect to the formal model.
• Evaluation. The assessment of an IT product against the Common Criteria using the
Common Criteria Evaluation Methodology to determine whether or not the claims
made are justified; or the assessment of a protection profile against the Common
Criteria using the Common Evaluation Methodology to determine if the Profile is
complete, consistent, technically sound and hence suitable for use as a statement of
requirements for one or more TOEs that may be evaluated.
• Evaluation Evidence. Any tangible resource (information) required from the sponsor
or developer by the evaluator to perform one or more evaluation activities.
• Feature. Part of a product that is either included with the product or can be ordered
separately.
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• Target of Evaluation (TOE). A group of IT products configured as an IT system, or
an IT product, and associated documentation that is the subject of a security evaluation
under the CC.
• Validation. The process carried out by the CCEVS Validation Body leading to the
issue of a Common Criteria certificate.
• Validation Body. A governmental organization responsible for carrying out validation
and for overseeing the day-to-day operation of the NIAP Common Criteria Evaluation
and Validation Scheme.
14 Bibliography
The Validation Team used the following documents to produce this Validation Report:
[1] Common Criteria for Information Technology Security Evaluation: Part 1:
Introduction and General Model, Version 3.1, Revision 5, April 2017.
[2] Common Criteria for Information Technology Security Evaluation Part 2: Security
functional components, Version 3.1, Revision 5, April 2017.
[3] Common Criteria for Information Technology Security Evaluation Part 3: Security
assurance components, Version 3.1 Revision 5, April 2017.
[4] collaborative Protection Profile for Network Devices, Version 2.2e, 23 March 2020
(NDcPP22e),
[5] Extreme Networks, Inc. SLX Product Series operating with Version 20.2.1aa
Security Target, Version 0.6, July 19, 2021 (ST)
[6] Assurance Activity Report for Extreme Networks, Inc. SLX Product Series
operating with Version 20.2.1aa, Version 0.4, July 19, 2021 (AAR)
[7] Detailed Test Report for Extreme Networks, Inc. SLX Product Series operating with
Version 20.2.1aa, Version 0.4, July 19, 2021 (DTR)
[8] Evaluation Technical Report for Extreme Networks, Inc. SLX Product Series
operating with Version 20.2.1aa, ETR Version 0.4, July 19, 2021 (ETR)
[9] Extreme SLX-OS Common Criteria Configuration Guide, 20.2.1aa, Version 2.5.2,
7 July 2021