BSI-DSZ-CC-1177-2025
for
L4Re Secure Separation Kernel CC Version 1.0.1
from
Kernkonzept GmbH
BSI - Bundesamt für Sicherheit in der Informationstechnik, Postfach 20 03 63, D-53133 Bonn
Phone +49 (0)228 99 9582-0, Fax +49 (0)228 9582-5477, Infoline +49 (0)228 99 9582-111
Certification Report V1.0 CC-Zert-327 V5.48
BSI-DSZ-CC-1177-2025 (*)
Operating System
L4Re Secure Separation Kernel CC, Version 1.0.1
from Kernkonzept GmbH
Functionality: Product specific Security Target
Common Criteria Part 2 conformant
Assurance: Common Criteria Part 3 conformant
EAL 4 augmented by ALC_FLR.3
valid until: 17 February 2030
The IT Product identified in this certificate has been evaluated at an approved evaluation
facility using the Common Methodology for IT Security Evaluation (CEM), Version 3.1
extended by Scheme Interpretations for conformance to the Common Criteria for IT
Security Evaluation (CC), Version 3.1. CC and CEM are also published as ISO/IEC 15408
and ISO/IEC 18045.
(*) This certificate applies only to the specific version and release of the product in its
evaluated configuration and in conjunction with the complete Certification Report and
Notification. For details on the validity see Certification Report part A chapter 5.
The evaluation has been conducted in accordance with the provisions of the certification
scheme of the German Federal Office for Information Security (BSI) and the conclusions
of the evaluation facility in the evaluation technical report are consistent with the
evidence adduced.
This certificate is not an endorsement of the IT Product by the Federal Office for
Information Security or any other organisation that recognises or gives effect to this
certificate, and no warranty of the IT Product by the Federal Office for Information
Security or any other organisation that recognises or gives effect to this certificate, is
either expressed or implied.
Bonn, 18 February 2025
For the Federal Office for Information Security
Sandro Amendola
Director-General
SOGIS
Recognition Agreement
Common Criteria
Recognition Arrangement
recognition for components
up to EAL 2 and ALC_FLR
only
Bundesamt für Sicherheit in der Informationstechnik
Godesberger Allee 185-189 - D-53175 Bonn - Postfach 20 03 63 - D-53133 Bonn
Phone +49 (0)228 99 9582-0 - Fax +49 (0)228 9582-5477 - Infoline +49 (0)228 99 9582-111
Certification Report BSI-DSZ-CC-1177-2025
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BSI-DSZ-CC-1177-2025 Certification Report
Contents
A. Certification.....................................................................................................................6
1. Preliminary Remarks....................................................................................................6
2. Specifications of the Certification Procedure...............................................................6
3. Recognition Agreements..............................................................................................7
4. Performance of Evaluation and Certification................................................................8
5. Validity of the Certification Result.................................................................................8
6. Publication...................................................................................................................9
B. Certification Results......................................................................................................10
1. Executive Summary...................................................................................................11
2. Identification of the TOE............................................................................................12
3. Security Policy...........................................................................................................13
4. Assumptions and Clarification of Scope.....................................................................13
5. Architectural Information............................................................................................13
6. Documentation...........................................................................................................14
7. IT Product Testing......................................................................................................14
8. Evaluated Configuration.............................................................................................16
9. Results of the Evaluation...........................................................................................16
10. Obligations and Notes for the Usage of the TOE.....................................................17
11. Security Target.........................................................................................................17
12. Definitions................................................................................................................17
13. Bibliography.............................................................................................................19
C. Excerpts from the Criteria.............................................................................................21
D. Annexes........................................................................................................................ 22
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Certification Report BSI-DSZ-CC-1177-2025
A. Certification
1. Preliminary Remarks
Under the BSIG1
Act, the Federal Office for Information Security (BSI) has the task of
issuing certificates for information technology products.
Certification of a product is carried out on the instigation of the vendor or a distributor,
hereinafter called the sponsor.
A part of the procedure is the technical examination (evaluation) of the product according
to the security criteria published by the BSI or generally recognised security criteria.
The evaluation is normally carried out by an evaluation facility recognised by the BSI or by
BSI itself.
The result of the certification procedure is the present Certification Report. This report
contains among others the certificate (summarised assessment) and the detailed
Certification Results.
The Certification Results contain the technical description of the security functionality of
the certified product, the details of the evaluation (strength and weaknesses) and
instructions for the user.
2. Specifications of the Certification Procedure
The certification body conducts the procedure according to the criteria laid down in the
following:
● Act on the Federal Office for Information Security1
● BSI Certification and Approval Ordinance2
● BMI Regulations on Ex-parte Costs 3
● Special decrees issued by the Bundesministerium des Innern und für Heimat (Federal
Ministry of the Interior and Community)
● DIN EN ISO/IEC 17065 standard
● BSI certification: Scheme documentation describing the certification process (CC-
Produkte) [3]
● BSI certification: Scheme documentation on requirements for the Evaluation Facility, its
approval and licencing process (CC-Stellen) [3]
● Common Criteria for IT Security Evaluation (CC), Version 3.14
[1] also published as
ISO/IEC 15408
1
Act on the Federal Office for Information Security (BSI-Gesetz - BSIG) of 14 August 2009,
Bundesgesetzblatt I p. 2821
2
Ordinance on the Procedure for Issuance of Security Certificates and approval by the Federal Office for
Information Security (BSI-Zertifizierungs- und -Anerkennungsverordnung - BSIZertV) of 17 December
2014, Bundesgesetzblatt 2014, part I, no. 61, p. 2231
3
BMI Regulations on Ex-parte Costs - Besondere Gebührenverordnung des BMI für individuell
zurechenbare öffentliche Leistungen in dessen Zuständigkeitsbereich (BMIBGebV), Abschnitt 7 (BSI-
Gesetz) - dated 2 September 2019, Bundesgesetzblatt I p. 1365
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BSI-DSZ-CC-1177-2025 Certification Report
● Common Methodology for IT Security Evaluation (CEM), Version 3.1 [2] also published
as ISO/IEC 18045
● BSI certification: Application Notes and Interpretation of the Scheme (AIS) [4]
3. Recognition Agreements
In order to avoid multiple certification of the same product in different countries a mutual
recognition of IT security certificates - as far as such certificates are based on ITSEC or
CC - under certain conditions was agreed.
3.1. European Recognition of CC – Certificates (SOGIS-MRA)
The SOGIS-Mutual Recognition Agreement (SOGIS-MRA) Version 3 became effective in
April 2010. It defines the recognition of certificates for IT-Products at a basic recognition
level and, in addition, at higher recognition levels for IT-Products related to certain SOGIS
Technical Domains only.
The basic recognition level includes Common Criteria (CC) Evaluation Assurance Levels
EAL 1 to EAL 4. For "Smartcards and similar devices" a SOGIS Technical Domain is in
place. For "HW Devices with Security Boxes" a SOGIS Technical Domains is in place, too.
In addition, certificates issued for Protection Profiles based on Common Criteria are part of
the recognition agreement.
The current list of signatory nations and approved certification schemes, details on
recognition, and the history of the agreement can be seen on the website at
https://www.sogis.eu.
The SOGIS-MRA logo printed on the certificate indicates that it is recognised under the
terms of this agreement by the related bodies of the signatory nations. A disclaimer
beneath the logo indicates the specific scope of recognition.
This certificate is recognized under SOGIS-MRA for all assurance components selected.
3.2. International Recognition of CC – Certificates (CCRA)
The international arrangement on the mutual recognition of certificates based on the CC
(Common Criteria Recognition Arrangement, CCRA-2014) has been ratified on 08
September 2014. It covers CC certificates based on collaborative Protection Profiles (cPP)
(exact use), CC certificates based on assurance components up to and including EAL 2 or
the assurance family Flaw Remediation (ALC_FLR) and CC certificates for Protection
Profiles and for collaborative Protection Profiles (cPP).
The current list of signatory nations and approved certification schemes can be seen on
the website: https://www.commoncriteriaportal.org.
The Common Criteria Recognition Arrangement logo printed on the certificate indicates
that this certification is recognised under the terms of this agreement by the related bodies
of the signatory nations. A disclaimer beneath the logo indicates the specific scope of
recognition.
This certificate is recognized according to the rules of CCRA-2014, i. e. up to and including
CC part 3 EAL 2 and ALC_FLR components.
4
Proclamation of the Bundesministerium des Innern und für Heimat of 12 February 2007 in the
Bundesanzeiger dated 23 February 2007, p. 3730
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Certification Report BSI-DSZ-CC-1177-2025
4. Performance of Evaluation and Certification
The certification body monitors each individual evaluation to ensure a uniform procedure, a
uniform interpretation of the criteria and uniform ratings.
The product L4Re Secure Separation Kernel CC, Version 1.0.1 has undergone the
certification procedure at BSI.
The evaluation of the product L4Re Secure Separation Kernel CC, Version 1.0.1 was
conducted by atsec information security GmbH. The evaluation was completed on 11
February 2025. atsec information security GmbH is an evaluation facility (ITSEF)5
recognised by the certification body of BSI.
For this certification procedure the applicant is: Kernkonzept GmbH.
The product was developed by: Kernkonzept GmbH.
The certification is concluded with the comparability check and the production of this
Certification Report. This work was completed by the BSI.
5. Validity of the Certification Result
This Certification Report applies only to the version of the product as indicated. The
confirmed assurance package is valid on the condition that
● all stipulations regarding generation, configuration and operation, as given in the
following report, are observed,
● the product is operated in the environment described, as specified in the following report
and in the Security Target.
For the meaning of the assurance components and assurance levels please refer to CC
itself. Detailed references are listed in part C of this report.
The Certificate issued confirms the assurance of the product claimed in the Security Target
at the date of certification. As attack methods evolve over time, the resistance of the
certified version of the product against new attack methods needs to be re-assessed.
Therefore, the sponsor should apply for the certified product being monitored within the
assurance continuity program of the BSI Certification Scheme (e.g. by a re-assessment or
re-certification). Specifically, if results of the certification are used in subsequent evaluation
and certification procedures, in a system integration process or if a user's risk
management needs regularly updated results, it is recommended to perform a re-
assessment on a regular e.g. annual basis.
In order to avoid an indefinite usage of the certificate when evolved attack methods would
require a re-assessment of the products resistance to state of the art attack methods, the
maximum validity of the certificate has been limited. The certificate issued on 18 February
2025 is valid until 17 February 2030. Validity can be re-newed by re-certification.
The owner of the certificate is obliged:
1. when advertising the certificate or the fact of the product's certification, to refer to
the Certification Report as well as to provide the Certification Report, the Security
Target and user guidance documentation mentioned herein to any customer of the
product for the application and usage of the certified product,
5
Information Technology Security Evaluation Facility
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BSI-DSZ-CC-1177-2025 Certification Report
2. to inform the Certification Body at BSI immediately about vulnerabilities of the
product that have been identified by the developer or any third party after issuance
of the certificate,
3. to inform the Certification Body at BSI immediately in the case that security relevant
changes in the evaluated life cycle, e.g. related to development and production sites
or processes, occur, or the confidentiality of documentation and information related
to the Target of Evaluation (TOE) or resulting from the evaluation and certification
procedure where the certification of the product has assumed this confidentiality
being maintained, is not given any longer. In particular, prior to the dissemination of
confidential documentation and information related to the TOE or resulting from the
evaluation and certification procedure that do not belong to the deliverables
according to the Certification Report part B, or for those where no dissemination
rules have been agreed on, to third parties, the Certification Body at BSI has to be
informed.
In case of changes to the certified version of the product, the validity can be extended to
the new versions and releases, provided the sponsor applies for assurance continuity (i.e.
re-certification or maintenance) of the modified product, in accordance with the procedural
requirements, and the evaluation does not reveal any security deficiencies.
6. Publication
The product L4Re Secure Separation Kernel CC, Version 1.0.1 has been included in the
BSI list of certified products, which is published regularly (see also Internet:
https://www.bsi.bund.de and [5]). Further information can be obtained from BSI-Infoline
+49 228 9582-111.
Further copies of this Certification Report can be requested from the developer6
of the
product. The Certification Report may also be obtained in electronic form at the internet
address stated above.
6
Kernkonzept GmbH
Buchenstraße 16 b
01097 Dresden
Deutschland
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Certification Report BSI-DSZ-CC-1177-2025
B. Certification Results
The following results represent a summary of
● the Security Target of the sponsor for the Target of Evaluation,
● the relevant evaluation results from the evaluation facility, and
● complementary notes and stipulations of the certification body.
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BSI-DSZ-CC-1177-2025 Certification Report
1. Executive Summary
The Target of Evaluation (TOE) is the L4Re Secure Separation Kernel CC, Version 1.0.1
(L4Re SSK). L4Re SSK is a distribution of the open-source L4Re Operating System
Framework. As such it is based on the L4Re Microkernel. The L4Re Microkernel is a 3rd-
generation microkernel with a state-of-the-art capability-based mandatory access control
security model. It allows the separation of applications into different security domains,
information flow control and, subject to access control, dynamic assignment of resources
and communication channels. Further the L4Re Microkernel supports static workloads
alongside dynamic workloads, which allows to start, restart and shutdown applications
during runtime.
L4Re SSK is configured to act as a separation kernel, to provide the security features
claimed by the ST. The TOE supports native applications as well as virtual machines
(VMs). Access to every resource including but not limited to memory, hardware devices
and CPU cores is protected by capabilities. Applications and VMs can only access a
resource if they possess a capability with suitable permissions for that resource.
The Security Target [6] is the basis for this certification.
The TOE Security Assurance Requirements (SAR) are based entirely on the assurance
components defined in Part 3 of the Common Criteria (see part C or [1], Part 3 for details).
The TOE meets the assurance requirements of the Evaluation Assurance Level EAL 4
augmented by ALC_FLR.3.
The TOE Security Functional Requirements (SFR) relevant for the TOE are outlined in the
Security Target [6], chapter 6. They are all selected from Common Criteria Part 2. Thus the
TOE is CC Part 2 conformant.
The TOE Security Functional Requirements are implemented by the following TOE
Security Functionality:
TOE Security
Functionality
Addressed issue
Separation of
Compartments
Compartments can only access those devices that are assigned to them in the initial
configuration. Unauthorized memory accesses via DMA as well as device to device
communications are prevented by utilizing appropriate hardware features (IOMMUs
and PCI-ACS).
Information Flow
Control
The communication channels present in the initial configuration determine the possible
information flow between compartments for the entire runtime. Compartments can be
configured to be isolated from each other (strong separation), to exchange data but no
capabilities (capability separation), or to exchange data and capabilities (address
space separation). Special purpose information flow properties can be achieved by
connecting two compartments only via a compartment communication proxy.
System
Management
The TOE configuration is defined with Lua scripts which allows the definition of objects
and subjects (i.e. compartments) and to assign objects to subjects. The TOE does not
provide management interfaces that allow system configuration at runtime.
Table 1: TOE Security Functionalities
For more details please refer to the Security Target [6], chapter 7.
The assets to be protected by the TOE are defined in the Security Target [6], chapter 3.1.1.
Based on these assets the TOE Security Problem is defined in terms of Assumptions,
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Certification Report BSI-DSZ-CC-1177-2025
Threats and Organisational Security Policies. This is outlined in the Security Target [6],
chapter 3.
This certification covers the configurations of the TOE as outlined in chapter 8.
The vulnerability assessment results as stated within this certificate do not include a rating
for those cryptographic algorithms and their implementation suitable for encryption and
decryption (see BSIG Section 9, Para. 4, Clause 2).
The certification results only apply to the version of the product indicated in the certificate
and on the condition that all the stipulations are kept as detailed in this Certification
Report. This certificate is not an endorsement of the IT product by the Federal Office for
Information Security (BSI) or any other organisation that recognises or gives effect to this
certificate, and no warranty of the IT product by BSI or any other organisation that
recognises or gives effect to this certificate, is either expressed or implied.
2. Identification of the TOE
The Target of Evaluation (TOE) is called:
L4Re Secure Separation Kernel CC, Version 1.0.1
The following table outlines the TOE deliverables:
No Type Identifier Release Form of Delivery
1 SW l4re_ssk_cc_lx2160a.zip (Hashwert:
f2b9256e72b2317acc51cd72e8743edb42c75f37)
1.0.1 Compressed zip archive for
LX2160A with SMMU
2 SW l4re_ssk_cc_x86_virt.zip (Hashwert:
057aff5ed3a4a4ba8f642e47298f28e9997c9464)
1.0.1 Compressed zip archive for x86
with VT-x enabled
3 SW l4re_ssk_cc_x86_novirt.zip (Hashwert:
433edf0f54fd869d515ec8f6524de48060583657)
1.0.1 Compressed zip archive for
with VT-x disabled
4 Doc l4re_ssk_cc_customer_doc.zip 1.0.1 Compressed zip archive of TOE
documentation (see #6 and #7)
5 Doc l4re_ssk_cc_interface_and_usage_documentatio
n.zip
1.0.1 Compressed zip archive L4Re
Interface and Usage
Documentation; separately
available
6 Doc L4Re Configuration Guidance.pdf 14 Guidance included in #4
7 Doc Development Guidance for a Compartment
Communication Proxy based on L4Re.pdf
7 Guidance included in #4
Table 2: Deliverables of the TOE
As the TOE consists only of Software and Documentation components but no hardware
components, delivery of physical items is not applicable. The TOE is delivered to the
customer either via remote access to the respective directory or as download, in a way
preserving authenticity, confidentiality and integrity. Note that the TOE is usually not
delivered to end users. It is rather made available to integrators responsible for integration
of the TOE as underlying platform into their products. That integration task is not a part of
the evaluation.
The TOE is delivered in several signed archives, one archive for each configuration and an
additional archive with documentation and configuration-independent code. Each archive
contains a VERSION file. The configuration-specific archives contain the compiled TOE
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BSI-DSZ-CC-1177-2025 Certification Report
components for one particular configuration and hardware architecture. Before using any
of the archives, the integrator must check the signature of the archive with the gpg key
provided by Kernkonzept, and check that the version matches the latest version
announced by Kernkonzept.
3. Security Policy
The security policy enforced is defined by the selected set of Security Functional
Requirements and implemented by the TOE. The TOE implements a capability-based
access control policy to control resource access by applications and virtual machines. The
capability-based access control is also the basis for an information flow control between
the mentioned applications / VMs. Specific details concerning the mentioned security
policies can be found in sections 7.1 and 7.2 of [6].
4. Assumptions and Clarification of Scope
The Assumptions defined in the Security Target and some aspects of Threats and
Organisational Security Policies are not covered by the TOE itself. These aspects lead to
specific security objectives to be fulfilled by the TOE-Environment. The following topics are
of relevance:
OE.HARDWARE The underlying hardware, firmware and bootloader needed by the TOE
to guarantee secure operations fulfil the requirements, as explained in
the TOE User Manuals and stated in section 1.3.5 [of [ST].]. They are
working correctly and have no undocumented or unintended security
critical side effect on the functions of the TOE.
OE.PHYSICAL The IT environment provides the TOE with appropriate physical
security that is commensurate with the value of the IT assets protected
by the TOE.
OE.NOEVIL The integrators are trustworthy, act according to the guidance
documentation, and are sufficiently qualified for this task.
Table 3: Security objectives for the operational environment
Details can be found in the Security Target [6], chapter 4.2.
5. Architectural Information
L4Re Secure Separation Kernel CC, Version 1.0.1 is a microkernel-based operating
system, where the functionality is split among the operating system kernel and multiple
user land applications and that is configured to work as a separation kernel. Only the L4Re
Microkernel runs in the most privileged CPU mode, where it provides the basic services
needed to implement use-case-specific services and policies in isolated user land
applications. This system architecture combined with the state-of-the-art, capability-based
mandatory access control allows L4Re SSK to efficiently implement the Principle of Least
Authority (POLA), which enables Zero Trust.
The L4Re Secure Separation Kernel CC, Version 1.0.1 consists of 7 components, 2 of
which are optional. The core is the L4Re Microkernel, which provides capability-based
access control, scheduling, secure memory management and inter-process
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Certification Report BSI-DSZ-CC-1177-2025
communication (IPC) which separates user-level components by employing hardware
features for spatial and temporal isolation.
The non-optional user-level components Sigma0, Moe, Ned, and Io provide core system
features and are implemented in an unprivileged CPU mode on the basis of the L4Re
Microkernel. These features include user-space memory management, secure device
access, and scriptable application workload booting. The two optional components are the
compartment communication proxies virtio-net-switch and NVMe server. The virtio-net-
switch provides a virtual network for those compartments that may communicate but must
not exchange capabilities. The NVMe server can provide persistent storage to several
compartments that are completely separated and which can not and must not
communicate with each other. The certification additionally includes a development
guidance for compartment communication proxies that enables users of the L4Re Secure
Separation Kernel CC, Version 1.0.1 to implement their own specialized compartment
communication proxies to securely connect compartments.
6. Documentation
The evaluated documentation as outlined in table 2 is being provided with the product to
the customer. This documentation contains the required information for secure usage of
the TOE in accordance with the Security Target.
Additional obligations and notes for secure usage of the TOE as outlined in chapter 10 of
this report have to be followed.
7. IT Product Testing
7.1. Test Configuration
The evaluator tests were executed together with the developer tests using the same test
harness employed by the developer.
The following test environment was used for conducting testing:
• Test system hardware: The evaluator verified that a hardware platform consistent to
the hardware stated in [6] was provided. Specifically, the following hardware was
made available to the evaluator:
◦ Intel: Shuttle DS10U7 with Intel Intel Core i7-8565U CPU (Broadwell
architecture) offering support for VT-x with EPT and Intel IOMMU. The evaluator
verified that VT-x, EPT and IOMMU were activated by the BIOS.
◦ ARM: R-Car-M3
◦ ARM: LX2160A with support for SMMU
• Test system software: The evaluator verified that the TOE binaries version 1.0.1
were provided along with the associated source code.
• Test case software: The evaluator verified that the TOE test cases were provided
with the TOE source code. The evaluator concluded that the test case version is
therefore inherently consistent with the TOE software version.
To support the evaluator, the developer provided access to a build environment that allows
creation of the test case binaries from the developer's test case sources as well as the
evaluator independent test case sources.
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BSI-DSZ-CC-1177-2025 Certification Report
Based on the conducted analyses, the evaluator concluded that the test hardware,
software and test cases, and thus the test configuration was consistent with the
configuration under evaluation as specified in [6].
7.2. Developer Testing
The developer runs a test suite of more than 200 automated tests.
Testing Approach
The automated tests are API tests which test the TOE using its external interfaces, usually
a specific TOE subsystem or object functions. The tests usually only involve the Sigma0,
the kernel, and Moe. There are special scenario tests which involve a more complex setup
including proxy components like the NVMe server or virtio-net-switch.
Test Configuration
The automated tests are performed for each supported platform defined in the ST:
• x86_64 Intel CPU with Broadwell microarchitecture or later, support for VT-x with
EPT, Intel IOMMU, the latest microcode applied by the BIOS
• ARMv8 CPU: NXP LX2160A with support for ARM virtualization
Not all tests do apply for all platforms as some do verify platform-specific functions.
Verdict
All test results for the relevant test cases show a 'PASS' verdict.
7.3. Evaluator Testing
The evaluator conducted the independent testing by conducting the developer testing
jointly with the developer as well as executing independent tests. These independent tests
are fully automated test cases which apart from compiling and execution do not require
specific pre- or post-conditions.
Test Approach
The evaluator developed fully automated test cases. These test cases were written such
that they can be embedded into the developer's test harness which implies that the test
cases establish all required test conditions, execute the test operation and validate the
expected result. The user is returned only an indicator whether the test succeeded or
failed.
Test Configuration
The evaluator configured the TOE compliant to the guidance specifying the evaluated
configuration. For well-defined tests intending to validate the behaviour of TOE
components that are not configurable, the evaluator decided to have a configuration that is
not fully compliant to the evaluated configuration - the deviations have been reviewed to
not affect the tested functionality. In addition, all hardware systems outlined in the ST were
used during the testing. Each evaluator test case contained its own Ned LUA configuration
to specify its initial environment.
Verdict
All tests showed the expected results. Thus, the evaluator concluded that the TOE
behaves as expected with respect to the tested functionality.
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Certification Report BSI-DSZ-CC-1177-2025
7.4. Penetration Testing
The evaluator conducted the penetration testing by conducting the developer testing jointly
with the developer as well as executing independent tests.
Test Approach
The evaluator used the same test setup as for independent testing.
Test Configuration
The evaluator configured the TOE compliant to the guidance specifying the evaluated
configuration. For most of the test cases, however, the evaluator only instantiated the TOE
components that are intended to be tested to ensure that other TOE components cannot
interfere. This is considered appropriate, because the evaluated configuration does not
change the behaviour of the TOE components, but only ensures that compartments have a
disjoint set of resources. Yet, one test case complies with the evaluated configuration by
using the designated LUA service functions to establish separated compartments. In
addition, all hardware systems outlined in the ST were used during the testing. Each
evaluator test case contained its own Ned LUA configuration to specify its initial
environment.
Verdict
All tests showed the expected results. Thus, the evaluator concluded that the TOE
behaves as expected with respect to the tested functionality.
8. Evaluated Configuration
This certification covers the following configurations of the TOE: The Target of Evaluation
is the Kernkonzept L4Re Secure Separation Kernel CC, Version 1.0.1 (L4Re SSK). The
TOE is software only and is accompanied by guidance documentation. The items listed in
table 2 of this report represent the TOE.
9. Results of the Evaluation
9.1. CC specific results
The Evaluation Technical Report (ETR) [7] was provided by the ITSEF according to the
Common Criteria [1], the Methodology [2], the requirements of the Scheme [3] and all
interpretations and guidelines of the Scheme (AIS) [4] as relevant for the TOE.
The Evaluation Methodology CEM [2] was used.
As a result of the evaluation the verdict PASS is confirmed for the following assurance
components:
● All components of the EAL 4 package including the class ASE as defined in the CC (see
also part C of this report)
● The components ALC_FLR.3 augmented for this TOE evaluation.
The evaluation has confirmed:
● for the Functionality: Product specific Security Target
Common Criteria Part 2 conformant
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BSI-DSZ-CC-1177-2025 Certification Report
● for the Assurance: Common Criteria Part 3 conformant
EAL 4 augmented by ALC_FLR.3
The results of the evaluation are only applicable to the TOE as defined in chapter 2 and
the configuration as outlined in chapter 8 above.
9.2. Results of cryptographic assessment
The TOE does not include cryptographic mechanisms. Thus, no such mechanisms were
part of the assessment.
10. Obligations and Notes for the Usage of the TOE
The documents as outlined in table 2 contain necessary information about the usage of the
TOE and all security hints therein have to be considered. In addition all aspects of
Assumptions, Threats and OSPs as outlined in the Security Target not covered by the TOE
itself need to be fulfilled by the operational environment of the TOE.
The customer or user of the product shall consider the results of the certification within his
system risk management process. In order for the evolution of attack methods and
techniques to be covered, he should define the period of time until a re-assessment of the
TOE is required and thus requested from the sponsor of the certificate.
The limited validity for the usage of cryptographic algorithms as outlined in chapter 9 has
to be considered by the user and his system risk management process, too.
If available, certified updates of the TOE should be used. If non-certified updates or
patches are available the user of the TOE should request the sponsor to provide a re-
certification. In the meantime a risk management process of the system using the TOE
should investigate and decide on the usage of not yet certified updates and patches or
take additional measures in order to maintain system security.
11. Security Target
For the purpose of publishing, the Security Target [6] of the Target of Evaluation (TOE) is
provided within a separate document as Annex A of this report.
12. Definitions
12.1. Acronyms
ACS Access Control Services
AIS Application Notes and Interpretations of the Scheme
API Application Programming Interface
BIOS Basic Input/Output System
BSI Bundesamt für Sicherheit in der Informationstechnik / Federal Office for
Information Security, Bonn, Germany
BSIG BSI-Gesetz / Act on the Federal Office for Information Security
CCRA Common Criteria Recognition Arrangement
CC Common Criteria for IT Security Evaluation
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CEM Common Methodology for Information Technology Security Evaluation
cPP Collaborative Protection Profile
DMA Direct Memory Access
EAL Evaluation Assurance Level
EPT Extended Page Tables
ETR Evaluation Technical Report
IOMMU Input/Output Memory Management Unit
IPC Inter Process Communication
IRQ Interrupt Request
ITAS In-Task Service
IT Information Technology
ITSEF Information Technology Security Evaluation Facility
L4Re L4 Runtime-Environment
L4Re SSK L4Re Secure Separation Kernel CC 1.0.1
MMU Memory Management Unit
MMIO Memory-mapped I/O
NVMe Non-Volatile Memory (NVM) Express
PCI Peripheral Component Interconnect
PCIe PCI Express
PP Protection Profile
SAR Security Assurance Requirement
SFP Security Function Policy
SFR Security Functional Requirement
ST Security Target
TOE Target of Evaluation
TSF TOE Security Functionality
VT-x Intel® Virtualization Technology for x86 processors
12.2. Glossary
Augmentation - The addition of one or more requirement(s) to a package.
Collaborative Protection Profile - A Protection Profile collaboratively developed by an
International Technical Community endorsed by the Management Committee.
Extension - The addition to an ST or PP of functional requirements not contained in CC
part 2 and/or assurance requirements not contained in CC part 3.
Formal - Expressed in a restricted syntax language with defined semantics based on well-
established mathematical concepts.
Informal - Expressed in natural language.
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Object - A passive entity in the TOE, that contains or receives information, and upon which
subjects perform operations.
Package - named set of either security functional or security assurance requirements
Protection Profile - A formal document defined in CC, expressing an implementation
independent set of security requirements for a category of IT Products that meet specific
consumer needs.
Security Target - An implementation-dependent statement of security needs for a specific
identified TOE.
Semiformal - Expressed in a restricted syntax language with defined semantics.
Subject - An active entity in the TOE that performs operations on objects.
Target of Evaluation - An IT Product and its associated administrator and user guidance
documentation that is the subject of an Evaluation.
TOE Security Functionality - Combined functionality of all hardware, software, and
firmware of a TOE that must be relied upon for the correct enforcement of the SFRs.
13. Bibliography
[1] Common Criteria for Information Technology Security Evaluation, Version 3.1,
Part 1: Introduction and general model, Revision 5, April 2017
Part 2: Security functional components, Revision 5, April 2017
Part 3: Security assurance components, Revision 5, April 2017
https://www.commoncriteriaportal.org
[2] Common Methodology for Information Technology Security Evaluation (CEM),
Evaluation Methodology, Version 3.1, Rev. 5, April 2017,
https://www.commoncriteriaportal.org
[3] BSI certification: Scheme documentation describing the certification process (CC-
Produkte) and Scheme documentation on requirements for the Evaluation Facility,
approval and licencing (CC-Stellen), https://www.bsi.bund.de/zertifizierung
[4] Application Notes and Interpretations of the Scheme (AIS) as relevant for the TOE7
https://www.bsi.bund.de/AIS
[5] German IT Security Certificates (BSI 7148), periodically updated list published also
on the BSI Website, https://www.bsi.bund.de/zertifizierungsreporte
[6] Security Target BSI-DSZ-CC-1177-2025, Version 2.14, 2025-02-10, Security Target
for L4Re Secure Separation Kernel CC, Version 1.0.1, Kernkonzept GmbH
[7] Final Evaluation Technical Report, Version 2, 2025-02-04, atsec information security
GmbH, (confidential document)
7
specifically
• AIS 1 Anforderungen an Aufbau und Inhalt von Einzelprüfberichten für Evaluationen nach CC
• AIS 14 Anforderungen an Aufbau und Inhalt von Einzelprüfberichten für Evaluationen nach CC
• AIS 19 Anforderungen an Aufbau und Inhalt der Zusammenfassung des ETR (Evaluation Technical
Report) für Evaluationen nach CC (Common Criteria)
• AIS 23 Zusammentragen von Nachweisen der Entwickler (Collection of Developer Evidence)
• AIS 32, Version 7, CC-Interpretationen im deutschen Zertifizierungsschema
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[8] L4Re Secure Separation Kernel CC, Version 1.0.1 Konfigurationsliste, Version 1.0,
2024-11-18, Kernkonzept GmbH (confidential document)
[9] L4Re Secure Boot Guidance, 2022-10-07, Kernkonzept GmbH
[10] L4Re Configuration Guidance, Version 13, 2024-08-19, Kernkonzept GmbH
[11] Development Guidance for a Compartment Communication Proxy based on L4Re,
Version 7, Date 2024-10-21, Kernkonzept GmbH
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C. Excerpts from the Criteria
For the meaning of the assurance components and levels the following references to the
Common Criteria can be followed:
• On conformance claim definitions and descriptions refer to CC part 1 chapter 10.5
• On the concept of assurance classes, families and components refer to CC Part 3
chapter 7.1
• On the concept and definition of pre-defined assurance packages (EAL) refer to CC
Part 3 chapters 7.2 and 8
• On the assurance class ASE for Security Target evaluation refer to CC Part 3
chapter 12
• On the detailed definitions of the assurance components for the TOE evaluation
refer to CC Part 3 chapters 13 to 17
• The table in CC part 3 , Annex E summarizes the relationship between the
evaluation assurance levels (EAL) and the assurance classes, families and
components.
The CC are published at https://www.commoncriteriaportal.org/cc/
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D. Annexes
List of annexes of this certification report
Annex A: Security Target provided within a separate document.
Note: End of report
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