BSI-DSZ-CC-0918-V3-2022 for CONEXA 3.0, Version 1.2 from Theben AG 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 V5.41 BSI-DSZ-CC-0918-V3-2022 (*) CONEXA 3.0 Version 1.2 from Theben AG PP Conformance: Protection Profile for the Gateway of a Smart Metering System, Version 1.3, 31 March 2014, BSI- CC-PP-0073-2014 Functionality: PP conformant Common Criteria Part 2 extended Assurance: Common Criteria Part 3 conformant EAL 4 augmented by ALC_FLR.2, AVA_VAN.5 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 and by advice of the Certification Body for components beyond EAL 5 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, 24 January 2022 For the Federal Office for Information Security Sandro Amendola L.S. Head of Division 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 SOGIS Recognition Agreement for components up to EAL 4 Common Criteria Recognition Arrangement recognition for components up to EAL 2 and ALC_FLR only Certification Report BSI-DSZ-CC-0918-V3-2022 This page is intentionally left blank. 4 / 25 BSI-DSZ-CC-0918-V3-2022 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.............................................................................................13 3. Security Policy............................................................................................................14 4. Assumptions and Clarification of Scope.....................................................................14 5. Architectural Information.............................................................................................14 6. Documentation...........................................................................................................15 7. IT Product Testing.......................................................................................................15 8. Evaluated Configuration.............................................................................................17 9. Results of the Evaluation............................................................................................17 10. Obligations and Notes for the Usage of the TOE.....................................................19 11. Security Target..........................................................................................................19 12. Definitions.................................................................................................................19 13. Bibliography..............................................................................................................21 C. Excerpts from the Criteria..............................................................................................24 D. Annexes.........................................................................................................................25 5 / 25 Certification Report BSI-DSZ-CC-0918-V3-2022 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 (Federal Ministry of the Interior) ● 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] 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 6 / 25 BSI-DSZ-CC-0918-V3-2022 Certification Report ● Common Criteria for IT Security Evaluation (CC), Version 3.14 [1] also published as ISO/IEC 15408. ● 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 according to the rules of SOGIS-MRA, i.e. up to and including CC part 3 EAL 4 components. The evaluation contained the component AVA_VAN.5 that is not mutually recognised in accordance with the provisions of the SOGIS MRA. For mutual recognition the EAL 4 components of these assurance families are relevant. 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 4 Proclamation of the Bundesministerium des Innern of 12 February 2007 in the Bundesanzeiger dated 23 February 2007, p. 3730 7 / 25 Certification Report BSI-DSZ-CC-0918-V3-2022 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+ ALC_FLR components. 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 CONEXA 3.0, Version 1.2 has undergone the certification procedure at BSI. This is a re-certification based on BSI-DSZ-CC-0918-V2-2021. Specific results from the evaluation process BSI-DSZ-CC-0918-V2-2021 were re-used. The evaluation of the product CONEXA 3.0, Version 1.2 was conducted by TÜV Informationstechnik GmbH. The evaluation was completed on 19 January 2022. TÜV Informationstechnik GmbH is an evaluation facility (ITSEF)5 recognised by the certification body of BSI. For this certification procedure the applicant is: Theben AG. The product was developed by: Theben AG. 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 24 January 2022 is valid until 23 January 2030. Validity can be re-newed by re-certification. 5 Information Technology Security Evaluation Facility 8 / 25 BSI-DSZ-CC-0918-V3-2022 Certification Report 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, 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 CONEXA 3.0, Version 1.2 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 Theben AG Hohenbergstraße 32 72401 Haigerloch 9 / 25 Certification Report BSI-DSZ-CC-0918-V3-2022 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. 10 / 25 BSI-DSZ-CC-0918-V3-2022 Certification Report 1. Executive Summary The Target of Evaluation (TOE) is the Smart Meter Gateway (SMGW) CONEXA 3.0, Version 1.2. It is an electronic unit comprising hardware, software and firmware used for collection, storage and provision of meter data from one or more meters of one or multiple commodities. The gateway connects a wide area network (WAN) with a network of devices of one or more smart metering devices (local metrological network, LMN) and the consumer home area network (HAN), which hosts controllable local systems (CLS). The security functionality of the TOE comprises protection of confidentiality, authenticity, integrity of data and information flow control mainly to protect the privacy of consumers, to ensure a reliable billing process and to protect the Smart Metering System and a corresponding large scale infrastructure of the smart grid. Besides a certified security module the hardware device also includes hardwired communication adapters which both are not part of the TOE but which are always inseparable parts of the delivered entity. The Security Target [6] is the basis for this certification. It is based on the certified Protection Profile Protection Profile for the Gateway of a Smart Metering System, Version 1.3, 31 March 2014, BSI-CC-PP-0073-2014 [8]. 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.2, AVA_VAN.5. The TOE Security Functional Requirements (SFR) relevant for the TOE are outlined in the Security Target [6], chapter 6.1-6.10. They are selected from Common Criteria Part 2 and some of them are newly defined. Thus the TOE is CC Part 2 extended. The TOE Security Functional Requirements are implemented by the following TOE Security Functionality: TOE Security Functionality Addressed issue SF.AU: Audit The TOE maintains three kinds of logs: . System Log, . Consumer Log, and . Calibration Log. The purpose of the System Log is to inform the Gateway Administrator and the Service Technician about the system status of the Smart Meter Gateway. The Consumer Log informs authorized Consumers about all information flows to the WAN, available Processing Profiles, billing relevant and other Meter Data. Within the Calibration Log only calibration relevant information is stored. SF.CR: Cryptography All connections between the TOE and external entities in WAN, HAN or LMN shall be cryptographically protected. Hence, the TOE allows only TLS 1.2 protected connections according to [RFC 5246] between the TOE and entities in the WAN or HAN. For TLS protected connections to the WAN, according to the requirements from [TR 03116-3] the elliptical 11 / 25 Certification Report BSI-DSZ-CC-0918-V3-2022 TOE Security Functionality Addressed issue curve BrainpoolP256r1 is useable only. Thus, the TOE supports the following symmetric cryptographic algorithm: AES-CBC with 128 bit key for encryption and decryption in accordance to [FIPS 197] and [NIST SP800-38A] and AES-CMAC with 128 bit key for integrity protection in accordance to [RFC 4493]. This method enforces that the TOE and the corresponding Meter have a common symmetric 128 bit key. SF.UD: User Data Protection The TOE is attached to three separated networks HAN, WAN and LMN. The interfaces to the different networks are physically separated. This TSF controls the access of all external entities in WAN, HAN and LMN to any information that is sent to, from or via the TOE or that is stored within the TOE. SF.IA: Identification & Authentication Each user who communicates with the TOE or receives data from the TOE shall be identified and authenticated before any action on behalf of that user, including receiving of data sent from the Gateway. SF.SM: Security Management The TOE offers a set of functions to manage and configure the TSF. Those security functions comprise • Management of devices in LMN and HAN, • Client management, • Maintenance of Processing Profiles, • Key- and Certificate-Management, • Firmware Update, • Wake-up configuration, • Monitoring, • Resetting of the TOE (restart), and • Audit Log configuration. SF.PR: Privacy This TSF assures the privacy of the Consumer by ensuring that authorized External Entities can only obtain data that is absolutely relevant for billing processes and the secure operation of the grid. SF.SP: Self-protection The TOE provides a set of self-protection mechanisms that in particular comprises the self-test of the TOE, detection of replay and physical attacks and the failure with preservation of a secure state. 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 3.2. Based on these assets the TOE Security Problem is defined in terms of Assumptions, Threats and Organisational Security Policies. This is outlined in the Security Target [6], chapters 3.3- 3.5. 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 12 / 25 BSI-DSZ-CC-0918-V3-2022 Certification Report 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: CONEXA 3.0, Version 1.2 The following table outlines the TOE deliverables: N o Type Identifier Release Form of Delivery 1 HW CONEXA 3.0 HW V01.00 Secure Delivery Procedure via transport service and installation by a service technician or personal hand over 2 SW SMGW Software v3.50.0-cc Pre-Installed on the HW 3 DOC Handbuch CONEXA 3.0 für den Gateway Administrator v2.9.0 7fae5dd0197d38e4fefc978a816e19e7ff 67f8329a77e94230bbc4554df71274 Download from https secured website 4 DOC Handbuch CONEXA 3.0 für den Service- Techniker v2.10.1 3f7cc9dcb5fae18ac17eb9d3f02658e76 fe292c7fbb01f0801480eca1abc58f7 Download from https secured website 5 DOC Handbuch CONEXA 3.0 für den Letztverbraucher v2.8.0 6a19d74602e1a776ccf43b4d4445e78d 04f1d831a7ac2f66e979b5eb428c345c Download from https secured website 6 DOC Conexa 3.0 Profilbeschreibungen v2.12 ad890a82827c9d58f2ac490bd769dc8e bd5789459b7e6f877396a8ff3878f34f Download from https secured website 7 DOC COSEM HTTP- Webservice v2.2 8abbabcaff546dbfc060d0100bd2fd6a5 b99988af99d9b97c759b22626dea8dd Download from https secured website 8 DOC Conexa 3.0 Logmeldungen v1.8.0 5c18e61a9dc0caa5485ec51f424078c1 35225cc196f2d3c8fd2e681ee9cf69e0 Download from https secured website 9 DOC Schnittstellenbe- schreibung IF_GW_CON v1.4 26c821592d7245e29ce91fc25c5dacc0 c3310f2885fa9e1baff30d7e97103221 Download from https secured website 10 DOC Schnittstellenbe- schreibung IF_GW_SRV v1.4 ec094d7ff046c387e921bfdd2d4944330 83030745cc22cdf20824dc5f5feab99 Download from https secured website Table 2: Deliverables of the TOE The Smart Meter Gateways are delivered within a special and secure transport box (Phyloc Box) by a standard transportation service. The secure transport box can only be opened by authorized individuals by using a special key pad and a valid one time PIN. Due to the mandatory instructions of the developer it is not allowed to remove SMGWs from the 13 / 25 Certification Report BSI-DSZ-CC-0918-V3-2022 secure transport box outside a secure storage room (e.g. at the premise of the energy company) or at the place of installation at the consumers premise where it is installed by a service technician. All places where SMGWs will be stored during the delivery need to provide a basic protection against possible attackers (e.g. concrete walls, doors need to be locked, and a physical inventory needs to be performed). Thereby it is ensured that no manipulation of the SMGW can take place on the complete track of delivery (starting with the manufacturer, through the different stages of storages to the final place of installation). The TOE thereby consists of the main circuit board of the Smart Meter Gateway, the case and the seal. The correct hardware of the TOE can be identified by the identifier “HW V01.00”, which can be found on a laser engraving on the TOE. The firmware and software are pre-installed on the hardware and therefore also part of the physical delivery. They can be uniquely identified by all users by connecting to the TOE and using the commands described in the relevant guidance document. The guidance documents mentioned in Table 2 can be downloaded by a https secured website. The corresponding users can uniquely identify the guidance by checking the hash sum which is also included in the Security Target [6]. 3. Security Policy The Security Policy is expressed by the set of Security Functional Requirements and implemented by the TOE. It covers the following issues: Security audit, communication, cryptographic support, user data protection, identification and authentication, security management, privacy, protection of the TSF, trusted channels. 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: • Trustworthy authorised and authenticated external entities • Trustworthy and well-trained gateway administrators and service technicians • Basic level of physical protection by installation in a non-public environment within the premises of the consumer • Processing profiles are obtained from a trustworthy and reliable source only • Usage of certified Security Module for specific cryptographic services • Certification of firmware updates prior to installation in the SMGW • Reliability and availability of WAN network connections, trustworthiness and availability of time sources, assumptions on LMN and HAN network connections • Secure generation of ECC key pair and secure transmission to SMGW by the GWA Details can be found in the Security Target [6], chapter 4.2. 5. Architectural Information The TOE is subdivided into the following subsystems: 14 / 25 BSI-DSZ-CC-0918-V3-2022 Certification Report • Hardware: Includes the case of the SMGW, the seals and the electronic parts of the TOE and provides the physical basis as well as the passive physical protection for the TOE • OS: Includes the underlying operating system and provides the filesystem encryption, firewall functionality and mandatory access control • SMPF: Implements parts of the SMGW software and provides the functionality for system initialisation after the boot process, authentication of external entities, management of processing profiles and logging • Crypto: Implements parts of the SMGW software and provides the cryptographic functions of the TOE and the interface to the Security Module • Services: Implements parts of the SMGW software and provides the webserver for the requests send by the gateway administrator, service technician and consumer • WAN: Implements parts of the SMGW software and provides the wake-up-service, the communication channels for the GWA and the external entities. • HAN: Implements parts of the SMGW software and provides the communication channels to the external entities at the HAN interface • Calibration: Implements parts of the SMGW software and provides the communication channels to the meters at the LMN interface as well as the processing of the received meter data 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 There is only one final TOE configuration, which has to be tested. Nevertheless, the developer also provides an additional modification including SSH access for a minor set of testing. 7.1. TOE Test Configuration All developer tests in the context of the evaluation have been conducted using multiple TOE samples in two different configurations: • Final TOE with factory setting 15 / 25 Certification Report BSI-DSZ-CC-0918-V3-2022 • Instrumentalised TOE with SSH access for TOE manipulations and for firewall tests on the TOE 7.2. Developer Testing The developer’s testing approach was to test the TSFI systematically next to a deeper consideration of TOE subsystems, internal interactions and concrete SFR tests. The developer testing covered each TSFI, the case with its seals, the subsystem behaviour and interactions as well as all SFRs. The actual test results of the developer tests matched the expected results. Therefore the developer’s testing effort demonstrated that the security functionality and TSFI perform as specified. 7.3. Independent Evaluator Testing For the repetition of the developer tests the evaluation body chose to repeat a defined subset with the intent to cover the existing interfaces and the implemented security functionality in order to verify the correctness of the developer testing. For the independent tests the evaluation body chose to broadly cover all existing TSFI, whereby the focus was set to the WAN interface. The tests of the evaluation body are mainly performed on a stand-alone test equipment (Exceeding Solutions), containing approx. 3000 automated test cases in about 150 test suites developed by the lab, partitioned according to the SF established in the ST [6], Chapter 7. Using this environment, every necessary role with corresponding rights (Gateway Administrator, Service Technicians, Consumers and Meters) might be emulated at the appropriate interface. The overall test result is that no deviations were found between the expected and the actual test results. 7.4. Penetration Testing The evaluation body conducted penetration testing based on functional areas of concern derived from SFRs and architectural mechanisms. The penetration testing activities were performed as tests and as analytical tasks. Whenever an analysis was estimated to yield better results, the evaluators chose the analytical approach. Analytical activities were especially applied in the areas secure boot, self-protection, domain separation, kernel and system hardening as well as non- bypassability. Combined approaches were also applied. Furthermore, all differences between the certified SW version of the TOE during the previous certification (BSI-DSZ-CC-0918-V2) and the actual one under evaluation (BSI- DSZ-CC-0918-V3) were analysed via a detailed source code analysis discussed without further indication of potential vulnerabilities. The overall test result is that no deviations were found between the expected and the actual test results. No attack scenario with the attack potential High was actually successful in the TOE’s operational environment. 16 / 25 BSI-DSZ-CC-0918-V3-2022 Certification Report 8. Evaluated Configuration The TOE as identified in table 2 has been evaluated. There is only one configuration as the different variants of the communication adapters that are outside of the TOE scope run with the same HW and SW configuration of 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 for those components up to EAL 5 extended by advice of the Certification Body for components beyond EAL 5 [4] (AIS 34) and guidance specific for the technology of the product [4] (AIS 46, AIS 48). 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.2, AVA_VAN.5 augmented for this TOE evaluation. As the evaluation work performed for this certification procedure was carried out as a re- evaluation based on the certificate BSI-DSZ-CC-0918-V2-2021, re-use of specific evaluation tasks was possible. The focus of this re-evaluation was on implementing HKS 4 and HKS 5 communication scenarios. The evaluation has confirmed: ● PP Conformance: Protection Profile for the Gateway of a Smart Metering System, Version 1.3, 31 March 2014, BSI-CC-PP-0073-2014 [8] ● for the Functionality: PP conformant Common Criteria Part 2 extended ● for the Assurance: Common Criteria Part 3 conformant EAL 4 augmented by ALC_FLR.2, AVA_VAN.5 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 following table gives an overview of the cryptographic functionalities inside the TOE to enforce the security policy and outlines the standard of application where its specific appropriateness is stated. Purpose Cryptographic Mechanism Standard of Implementation Key Size in Bits Standard of Application Validity Period TLS cipher suite (key establishment, record layer encryption and TLS_ECDHE_ ECDSA_WITH _AES_128_CB C_SHA256, Cipher Suite: [RFC 5289], [RFC 5246] AES: [FIPS 197] CBC: [NIST SP800- AES: 128bit, 256bit EC: secp256r1, secp384r1, [TR03109] [20] 2026+ 17 / 25 Certification Report BSI-DSZ-CC-0918-V3-2022 Purpose Cryptographic Mechanism Standard of Implementation Key Size in Bits Standard of Application Validity Period integrity, peer authentication) TLS_ECDHE_ ECDSA_WITH _AES_256_CB C_SHA384, TLS_ECDHE_ ECDSA_WITH _AES_128_GC M_SHA256, TLS_ECDHE_ ECDSA_WITH _AES_256_GC M_SHA384 38A] HMAC: [RFC 2104] GCM: [NIST SP800- 38D] brainpoolPxxxr1: [RFC 5639] secpxxxr1: [RFC 5114] SHA: [FIPS 180-4] brainpoolP256r1, brainpoolP384r1, brainpoolP512r1 Key generation for CMS containers Key generation: ECKA-EG Key wrap: id- aes128-wrap Key wrap: [RFC 3394] Key generation: [TR 03111] 128bit [TR03109] [20] 2026+ Encryption / decryption /integrity of CMS container id-aes128-gcm, id-aes-CBC- CMAC-128 CMAC: [RFC 4493] GCM: [RFC 5084], [NIST SP800-38D] AES: [FIPS 197] CBC: [NIST SP800- 38A] 128bit [TR03109] [20] 2026+ Key generation for meter data AES-CMAC AES-CMAC: [RFC 4493] AES: [FIPS 197] 128bit [TR03109] [20] 2026+ Encryption/ decryption, integrity of meter data Encryption: AES-CBC Integrity protection: AES-CMAC AES-CMAC: [RFC 4493] AES: [FIPS 197] CBC: [NIST SP800- 38A] 128bit [TR03109] [20] 2026+ Hashing for signatures SHA-256, SHA- 384, SHA-512 SHA: [FIPS 180-4] - [TR-02102] [22] 2026+ Encryption / decryption, integrity of TSFI AES-128-CBC ESSIV:SHA256 AES: [FIPS 197] CBC: [NIST SP800- 38A] SHA: [FIPS 180-4] 128bit [TR-02102] [22] 2026+ Table 3: TOE cryptographic functionality The strength of the these cryptographic algorithms was not rated in the course of this certification procedure (see BSIG Section 9, Para. 4, Clause 2). According to TR-03109-3 [21] or TR-02102-1 [22], respectively, the algorithms are suitable for Smart Metering Systems. 18 / 25 BSI-DSZ-CC-0918-V3-2022 Certification Report 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 AIS Application Notes and Interpretations of the Scheme 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 CEM Common Methodology for Information Technology Security Evaluation CLS Controllable Local Systems CMS Cryptographic Message Syntax EAL Evaluation Assurance Level EMA Electro-Magnetic Analysis ETR Evaluation Technical Report GWA Gateway Administrator HAN Home Area Network HTTP Hypertext Transfer Protocol HTTPS Hypertext Transfer Protocol Secure 19 / 25 Certification Report BSI-DSZ-CC-0918-V3-2022 IP Internet Protocol IT Information Technology ITSEF Information Technology Security Evaluation Facility LMN Local Metrological Network MAC Message Authentication Code NTP Network Time Protocol PP Protection Profile SAR Security Assurance Requirement SF Security Function SFP Security Function Policy SFR Security Functional Requirement SMGW Smart Meter Gateway SMPF Smart Metering Platform Framework ST Security Target TOE Target of Evaluation TSF TOE Security Functionality WAN Wide Area Network 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. 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. 20 / 25 BSI-DSZ-CC-0918-V3-2022 Certification Report 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-0918-V3-2022, Version 1.92.2, 23.11.2021, Security Target (ASE) CONEXA 3.0 - Smart Meter Gateway, Theben AG [7] Evaluation Technical Report, Version 2, 17.01.2022, EVALUATION TECHNICAL REPORT SUMMARY (ETR SUMMARY), TÜV Informationstechnik GmbH, (confidential document) [8] Protection Profile for the Gateway of a Smart Metering System, Version 1.3, 31 March 2014, BSI-CC-PP-0073-2014 [9] Configuration list for the TOE HW: ALC_CMS.4 Konfigurationsliste Smart Meter Gateway CONEXA 3.0, Version 1.1, 2021-12-13, Theben AG (confidential document) [10] Configuration list for the TOE SW: ASSURANCE LIFE CYCLE – CONFIGURATION MANAGEMENT DER CONEXA 3.0 (ALC_CMS.4), v3.50.0-cc, 2021-12-13, Theben AG (confidential document) [11] Handbuch CONEXA 3.0 für Gateway Administrator, Version 2.9.0, 03.08.2021, Theben AG 7 specifically • AIS 34, Version 3, Evaluation Methodology for CC Assurance Classes for EAL 5+ (CCv2.3 & CCv3.1) and EAL 6 (CCv3.1) • AIS 46, Version 3, Informationen zur Evaluierung von kryptographischen Algorithmen und ergänzende Hinweise für die Evaluierung von Zufallszahlengeneratoren • AIS 48, Version 1.0, Anforderungen an die Prüfung von Sicherheitsetiketten 21 / 25 Certification Report BSI-DSZ-CC-0918-V3-2022 [12] Handbuch CONEXA 3.0 für den Letztverbraucher, Version 2.8.0, 04.08.2021, Theben AG [13] Handbuch CONEXA 3.0 für den Service-Techniker, Version 2.10.1, 06.09.2021, Theben AG [14] Conexa 3.0 Profilbeschreibungen, Version 2.12, 13.09.2021, Theben AG [15] COSEM HTTP-Webservice, Version 2.2, 27.03.2020, Theben AG [16] Conexa 3.0 Logmeldungen, Version 1.8.0, 05.08.2021, Theben AG [17] Schnittstellenbeschreibung IF_GW_CON, Version 1.4, 04 .04.2020, Theben AG [18] Schnittstellenbeschreibung IF_GW_SRV, Version 1.4, 04.04.2020, Theben AG [19] Impact Analysis Report, Version 0.9, 30.11.2021, Theben AG (confidential document) [20] Technische Richtlinie BSI TR-03109-1 Anforderungen an die Interoperabilität der Kommunikationseinheit eines intelligenten Messsystems, Version 1.1, 17. September 2021, Federal Office for Information Security [21] Technische Richtlinie BSI TR-03109-3 Kryptographische Vorgaben für die Infrastruktur von intelligenten Messsystemen, Version 1.1, 17 April 2014, Federal Office for Information Security [22] Technische Richtlinie BSI TR-02102-1 Kryptographische Verfahren: Empfehlungen und Schlüssellängen, Version 2020-01, 04 March 2020, Federal Office for Information Security [23] Standard of Implementation: BSI TR-03111, Elliptic Curve Cryptography (ECC), Version 2.10, 2018 [FIPS 180-4] NIST FIPS PUB 180-4: Secure Hash Standard (SHS). NIST, 2015. [FIPS 197] NIST FIPS PUB 197: Announcing the ADVANCED ENCRYPTION STANDARD (AES). NIST, 2001. [NIST SP800-38A] NIST SP800-38A: Recommendation for Block Cipher Modes of Operation: Methods and Techniques. NIST, 2001. [NIST SP800-38B] NIST SP800-38B: Recommendation for Block Cipher Modes of Operation: The CMAC Mode for Authentication. NIST, 2005. [NIST SP800-38D] NIST SP800-38D: Recommendation for Block Cipher Modes of Operation: Galois/Counter Mode (GCM) and GMAC. NIST, 2007. [RFC 2104] Network Working Group RFC 2104, H. Krawczyk et al.: HMAC: Keyed- Hashing for Message Authentication. Network Working Group, Feb. 1997 [RFC 3394] IETF RFC 3394, J. Schaad, R. Housley: Advanced Encryption Standard(AES) Key Wrap Algorithm. IETF, 2002. [RFC 4493] IETF RFC 4493, J. H. Song, J. Lee, T. Iwata: The AES-CMAC- Algorithm. IETF, 2006. [RFC 5084] IETF RFC 5084, R. Housley: Using AES-CCM and AES-GCM Authenticated Encryption in the Cryptographic Message Syntax (CMS). IETF, 2007. [RFC 5114] IETF RFC 5114, M. Lepinski, S. Kent: Additional Diffie-Hellman Groups for Use with IETFStandards, 2008 22 / 25 BSI-DSZ-CC-0918-V3-2022 Certification Report [RFC5246] RFC 5246 - The Transport Layer Security (TLS) Protocol, Version 1.2, Dierks & Rescorla - Standard Track, August 2008 [RFC 5289] IETF RFC 5289, E. Rescorla: TLS Elliptic Curve Cipher Suites with SHA-256/384 and AES Galois Counter Mode (GCM). IETF, 2008. [RFC 5639] IETF RFC 5639, M. Lochter, J. Merkle: Elliptic Curve Cryptography(ECC) Brainpool Standard Curves and Curve Generation. IETF, 2010 23 / 25 Certification Report BSI-DSZ-CC-0918-V3-2022 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/ 24 / 25 BSI-DSZ-CC-0918-V3-2022 Certification Report D. Annexes List of annexes of this certification report Annex A: Security Target provided within a separate document. Note: End of report 25 / 25