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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2018.3358 K01067037: BIG-IP tmsh vulnerability CVE-2018-15321 31 October 2018 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: F5 products Publisher: F5 Networks Operating System: Network Appliance Impact/Access: Overwrite Arbitrary Files -- Existing Account Resolution: Patch/Upgrade CVE Names: CVE-2018-15321 Original Bulletin: https://support.f5.com/csp/article/K01067037 - --------------------------BEGIN INCLUDED TEXT-------------------- K01067037: BIG-IP tmsh vulnerability CVE-2018-15321 Security Advisory Original Publication Date: Oct 31, 2018 Security Advisory Description When BIG-IP is licensed for Appliance mode, Admin and Resource administrator roles can by-pass BIG-IP Appliance mode restrictions to overwrite critical system files. (CVE-2018-15321) Attackers with a high-privilege level can overwrite critical system files, which in turn bypasses security controls that limit TMOS Shell (tmsh) commands. This scenario is possible when the Administrator or Resource Administrator roles are granted tmsh access. Resource Administrator roles must have tmsh access to perform this attack. Note: F5 does not consider the capability of Advanced Shell (bash) access in this vulnerability, as users granted that level of access can simply perform any command as root. This vulnerability is an issue for Appliance mode, users who are granted tmsh access, and for the Resource Administrator role when operating in standard, non-Appliance mode. Impact When the BIG-IP system is licensed for Appliance mode, Administrator and Resource Administrator roles can by-pass BIG-IP Appliance mode restrictions to overwrite critical system files. Security Advisory Status F5 Product Development has assigned ID 677088 (BIG-IP) and ID 705131 (BIG-IQ, Enterprise Manager, and iWorkflow) to this vulnerability. To determine if your product and version have been evaluated for this vulnerability, refer to the Applies to (see versions) box. To determine if your release is known to be vulnerable, the components or features that are affected by the vulnerability, and for information about releases or hotfixes that address the vulnerability, refer to the following table. For more information about security advisory versioning, refer to K51812227: Understanding Security Advisory versioning. +-------------------+------+----------+----------+----------+------+----------+ | | |Versions |Fixes | |CVSSv3|Vulnerable| |Product |Branch|known to |introduced|Severity |score^|component | | | |be |in | |1 |or feature| | | |vulnerable| | | | | +-------------------+------+----------+----------+----------+------+----------+ | |14.x |14.0.0 |14.0.0.3 | | | | | +------+----------+----------+ | | | |BIG-IP (LTM, AAM, |13.x |13.0.0 - |13.1.0.6 | | | | |AFM, Analytics, | |13.1.0 | | | | | |APM, ASM, DNS, Edge+------+----------+----------+ | |TMSH | |Gateway, FPS, GTM, |12.x |12.1.0 - |12.1.3.6 |Medium |4.4 |advanced | |Link Controller, | |12.1.3 | | | |shell | |PEM, +------+----------+----------+ | | | |WebAccelerator) | |11.6.0 - | | | | | | |11.x |11.6.3 |11.6.3.3 | | | | | | |11.2.1 - |11.5.7 | | | | | | |11.5.6 | | | | | +-------------------+------+----------+----------+----------+------+----------+ | | | | | | |TMSH | |Enterprise Manager |3.x |3.1.1 |None |Medium |4.4 |advanced | | | | | | | |shell | +-------------------+------+----------+----------+----------+------+----------+ | |6.x |None |Not | | | | | | | |applicable| | | | |BIG-IQ Centralized +------+----------+----------+ | |TMSH | |Management |5.x |5.0.0 - |None |Medium |4.4 |advanced | | | |5.4.0 | | | |shell | | +------+----------+----------+ | | | | |4.x |4.6.0 |None | | | | +-------------------+------+----------+----------+----------+------+----------+ |BIG-IQ Cloud and | | | | | |TMSH | |Orchestration |1.x |1.0.0 |None |Medium |4.4 |advanced | | | | | | | |shell | +-------------------+------+----------+----------+----------+------+----------+ | | |2.1.0 - | | | |TMSH | |F5 iWorkflow |2.x |2.3.0 |None |Medium |4.4 |advanced | | | | | | | |shell | +-------------------+------+----------+----------+----------+------+----------+ | |5.x |None |Not | | | | | | | |applicable|Not | | | |Traffix SDC +------+----------+----------+vulnerable|None |None | | |4.x |None |Not | | | | | | | |applicable| | | | +-------------------+------+----------+----------+----------+------+----------+ ^1 The CVSSv3 score link takes you to a resource outside of AskF5, and it is possible that the document may be removed without our knowledge. Security Advisory Recommended Actions If you are running a version listed in the Versions known to be vulnerable column, you can eliminate this vulnerability by upgrading to a version listed in the Fixes introduced in column. If the table lists only an older version than what you are currently running, or does not list a non-vulnerable version, then no upgrade candidate currently exists. Mitigation To mitigate this vulnerability, disable tmsh access for users with the Resource Administrator role, and grant administration access only by way of the BIG-IP Configuration utility. To complete this mitigation, perform one of the following procedures: Mitigate the vulnerability using the BIG-IP Configuration utility 1. Log in to the BIG-IP Configuration utility as the admin user. 2. Navigate to System > Users > User List. 3. Select the Resource Administrator you would like to modify. 4. Under Terminal Access select Disabled. 5. Click Update. Mitigate the vulnerability using tmsh 1. Log in to tmsh as the root user. 2. List the administrative users on your system. 3. Use the following command syntax to disable tmsh for a user. (Where <user> is the name of the user for whom you would like to disable tmsh.) modify /auth user <user> shell none For example: modify /auth user test-user shell none Supplemental Information o K51812227: Understanding Security Advisory versioning o K41942608: Overview of Security Advisory articles o K4602: Overview of the F5 security vulnerability response policy o K4918: Overview of the F5 critical issue hotfix policy o K9502: BIG-IP hotfix and point release matrix o K13123: Managing BIG-IP product hotfixes (11.x - 13.x) o K15106: Managing BIG-IQ product hotfixes o K15113: BIG-IQ hotfix matrix o K167: Downloading software and firmware from F5 o K9970: Subscribing to email notifications regarding F5 products o K9957: Creating a custom RSS feed to view new and updated documents o K21232150: Considerations for upgrading BIG-IQ or F5 iWorkflow systems - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to auscert@auscert.org.au and we will forward your request to the appropriate person. NOTE: Third Party Rights This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. The decision to follow or act on information or advice contained in this security bulletin is the responsibility of each user or organisation, and should be considered in accordance with your organisation's site policies and procedures. AusCERT takes no responsibility for consequences which may arise from following or acting on information or advice contained in this security bulletin. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. If downloading at a later date, it is recommended that the bulletin is retrieved directly from the author's website to ensure that the information is still current. Contact information for the authors of the original document is included in the Security Bulletin above. If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: https://www.auscert.org.au/bulletins/ =========================================================================== Australian Computer Emergency Response Team The University of Queensland Brisbane Qld 4072 Internet Email: auscert@auscert.org.au Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQIVAwUBW9kQ1WaOgq3Tt24GAQjRZxAAit43T0dF2ECh0IjNjlZ77UI5hOdG3fSQ u3BFOQKAOrLphNj8LuhyzYy+/ggrV7fWSPo+9/J3JSFkS1gSTI5IgwxRYXYYxqEr 4zgHCky18AWgZhTVE9ZWdHitUbRa3WBUoqtK6Mg+SCmWgfYuo4jMFTbg3NdBs4Wt Mx4jmjBOSvFCg/zr7CeFjwbbR9UTRUN/QIge2KLkawQOiR+MRrU+n694iN31i2PE qr38j7T5QBmWvoteuLK/Pf0ovcMSeHVb02MmFIsgRKEsy4vpZH8VTVzhhDNiCI6E TMWDeyF3QBpZvy1p9+WT0BjY3FiWGTfJ8H8BwZGb2qlgU5svlVzVonFAIUMQl701 fHqz2ympRTukrGWri2o8/XlXsmMYNACGPbLDN4GbTDZwdydut6yeIHjWmgXgbKET f04lVF6ijeoBvatMXWbu0Uy6hFKM6IWU4cGebYzMU3BIkpszALkH6vkrgqtS2LuU jE0e71vIshJo5XNsiXWGO01cUMLniPEdmrgDXnIwLytDSWVLoKGdr4RBO/x5JE3v xCUBBPI/Bx5r66IM/pnoqQg3HgiyQZHWm7iD4GOMgvu24tuls7h6cle36bTYuF37 Blr5pNkE+U3AgA2OX+611TebTMfzZc7YPHdP9Y7CP+3NcfrNiIVQ5tauADESp+2A XPsywnrGgWQ= =PXd1 -----END PGP SIGNATURE-----