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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2021.0980 TMM vulnerability CVE-2021-23007 22 March 2021 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: BIG-IP Products Publisher: F5 Networks Operating System: Network Appliance Impact/Access: Denial of Service -- Remote/Unauthenticated Resolution: Patch/Upgrade CVE Names: CVE-2021-23007 Original Bulletin: https://support.f5.com/csp/article/K37451543 - --------------------------BEGIN INCLUDED TEXT-------------------- K37451543: TMM vulnerability CVE-2021-23007 Original Publication Date: 20 Mar, 2021 Security Advisory Description When the Traffic Management Microkernel (TMM) process handles certain undisclosed traffic, it may start dropping all fragmented IP traffic. (CVE-2021-23007) Impact TMM incorrectly determines that the fragment memory limit has been reached and drops all fragments it receives, disrupting traffic to the BIG-IP system. You can determine if your system is impacted by running the tmctl ip_stat command from the BIG-IP command line and reviewing the output for an unusually large value in the frag_bytes_used column for a given TMM. You may observe that some TMM processes have high values and others do not. For example: rx_frag rx_frag_dropped err_frag_mem_limit_reached frag_bytes_used -------- --------------- -------------------------- -------------------- 46406517 508 0 0 rx_frag rx_frag_dropped err_frag_mem_limit_reached frag_bytes_used -------- --------------- -------------------------- -------------------- 44739031 217 0 0 rx_frag rx_frag_dropped err_frag_mem_limit_reached frag_bytes_used -------- --------------- -------------------------- -------------------- 39322744 8404728 8404628 18446744073709547072 rx_frag rx_frag_dropped err_frag_mem_limit_reached frag_bytes_used -------- --------------- -------------------------- -------------------- 33528060 15659496 15659334 18446744073709547072 rx_frag rx_frag_dropped err_frag_mem_limit_reached frag_bytes_used -------- --------------- -------------------------- -------------------- 46712180 157 0 0 rx_frag rx_frag_dropped err_frag_mem_limit_reached frag_bytes_used -------- --------------- -------------------------- -------------------- 38912369 10588696 10588558 18446744073709547072 Security Advisory Status F5 Product Development has assigned ID 1002561 (BIG-IP) 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, point 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. Note: After a fix is introduced for a vulnerable version, that fix applies to all subsequent point releases for that version and no additional fixes for that version will be listed in the table. For example, when a fix is introduced in 14.1.2.3, the fix applies to 14.1.2.4 and all later point releases. +-----------+------+----------+-------------------------------------+----------+------+----------+ | | |Versions | | |CVSSv3|Vulnerable| |Product |Branch|known to |Fixes introduced in |Severity |score^|component | | | |be | | |1 |or feature| | | |vulnerable| | | | | +-----------+------+----------+-------------------------------------+----------+------+----------+ | |16.x |16.0.1.1 |Hotfix-BIGIP-16.0.1.1.9.6-ENG.iso^2 | | | | | +------+----------+-------------------------------------+ | | | | |15.x |None |Not applicable | | | | | +------+----------+-------------------------------------+ | | | | |14.x |14.1.4 |Hotfix-BIGIP-14.1.4.0.120.11-ENG.iso^| | |TMM (IP | |BIG-IP (all| | |2 |Medium |5.3 |Fragment | |modules) +------+----------+-------------------------------------+ | |Handling) | | |13.x |None |Not applicable | | | | | +------+----------+-------------------------------------+ | | | | |12.x |None |Not applicable | | | | | +------+----------+-------------------------------------+ | | | | |11.x |None |Not applicable | | | | +-----------+------+----------+-------------------------------------+----------+------+----------+ | |8.x |None |Not applicable | | | | |BIG-IQ +------+----------+-------------------------------------+Not | | | |Centralized|7.x |None |Not applicable |vulnerable|None |None | |Management +------+----------+-------------------------------------+ | | | | |6.x |None |Not applicable | | | | +-----------+------+----------+-------------------------------------+----------+------+----------+ |F5OS |1.x |None |Not applicable |Not |None |None | | | | | |vulnerable| | | +-----------+------+----------+-------------------------------------+----------+------+----------+ |Traffix SDC|5.x |None |Not applicable |Not |None |None | | | | | |vulnerable| | | +-----------+------+----------+-------------------------------------+----------+------+----------+ ^1The CVSSv3 score link takes you to a resource outside of AskF5, and it is possible that the document may be removed without our knowledge. ^2You can download engineering hotfix releases from the following locations: o Engineering hotfix for 16.0.1.1: https://downloads.f5.com/esd/ecc.svsw= BIG-IP&pro=big-ip_v16.x&ver=16.0.1&container=HotFix-BIGIP-16.0.1.1.9.6-EHF9 o Engineering hotfix for 14.1.4: https://downloads.f5.com/esd/ecc.svsw= BIG-IP&pro=big-ip_v14.x&ver=14.1.4&container= HotFix-BIGIP-14.1.4.0.120.11-EHF120 Recommended Actions If you are running a version listed in the Versions known to be vulnerable column, you can eliminate this vulnerability by installing a version listed in the Fixes introduced in column. If the Fixes introduced in column does not list a version for your branch, then no update candidate currently exists for that branch and F5 recommends upgrading to a version with the fix (refer to the table). If the Fixes introduced in column lists a version prior to the one you are running, in the same branch, then your version should have the fix. Mitigation You can restart the TMM process to recover from the condition; however, this is not a permanent fix. To do so, perform the following procedure: Impact of procedure: Performing the following procedure causes a temporary traffic disruption while the TMM process restarts. You should perform this procedure only during a scheduled maintenance period. 1. Log in to the TMOS Shell (tmsh) by entering the following command: tmsh 2. To restart the TMM process, enter the following command: restart /sys service tmm Supplemental Information 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 - 16.x) 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 - --------------------------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 iQIVAwUBYFgFm+NLKJtyKPYoAQjeBQ/5ARSvrMQ9E7hIgzf4Q0uDJQwrpts/i2Vd /g9xc/Us5t9Wv8Pn+Jt91O3Lut55g8yFM8T3/U6YBpf2+kd5fbH0AK9vuriUxMy6 ANKaoyGrVaErv8t7jZOCXua4YxbQHhaJOm11xypuMhgFWYWQv87ouOfCCK2JBj2k hcf/vRChKDrSW+M9jA1Jv4pEa5+WJUTCLCZrVmg6WvPBGUwEVcUxdfRoe/RUsHWT V2EFtbwgvGLfzqwghUmHoqELpKaDYPnecEBW8+Mfjp1AcxpYR/OvQ8x9w3eBafHt dyP3AkngQXWwXeW4oVkFmEXeVktOnduCc4qEAIcI3PHEQZvynxQMJtM9HRwNY44E 1ZxuGNOWt/OUgAKA4VbV9FfInyuOBUGPXIyOfmw7bj+xIWqtBrclihs9Rd0Nb1qQ BeQWnhns36KFhYilszQH3tRg7XC/R4XSjZrIFJHV6OJByT02BrdW/Td8nXuiJfrM WcR4vfYVzr/d/BPa4J8+Gcd5T+aSpAJtSuoDNqzbLOF3XB49P8Klm2rquINZB4nP 17t7IVz+DDIXF5npeG8e3ECOZhLy0L9erzApCAhdumBvfe03IeI3d9TeZ86+GKRg RtNfzrbV5sIOZxuQ838crJfRjoXciYtbQpJoa5pEd2CAcAhTOxDQcVo1TAFlOYsn Qek8LpmTW64= =f3c/ -----END PGP SIGNATURE-----