Critical [CVE-2021-22991] On BIG-IP versions 16.0.x before 16.0.1.1, 15.1.x before 15.1.2.1, 14.1.x before 14.1.4, 13.1.x before 13.1.3.6, and 12.1.x…
This critical-severity F5 advisory covers CVE-2021-22991 affecting BIG-IP.
Android app · Google Play
Monitor future F5 CVEs from your phone.
Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.
Summary
On BIG-IP versions 16.0.x before 16.0.1.1, 15.1.x before 15.1.2.1, 14.1.x before 14.1.4, 13.1.x before 13.1.3.6, and 12.1.x before 12.1.5.3, undisclosed requests to a virtual server may be incorrectly handled by the Traffic Management Microkernel (TMM) URI normalization, which may trigger a buffer overflow, resulting in a DoS attack.
In certain situations, it may theoretically allow bypass of URL based access control or remote code execution (RCE). Note: Software versions which have reached End of Software Development (EoSD) are not evaluated.
CISA Known Exploited Vulnerability
- Listed:
- Jan 18, 2022 · federal remediation due Feb 1, 2022
- Required action:
- Apply updates per vendor instructions.
- Ransomware use:
- Unknown
KEV is a prioritization signal from CISA — remediation detail still comes from the vendor advisory.
- 16.0.x
- 15.1.x
- 14.1.x
- 13.1.x
- 12.1.x
Official advisory · high-confidence parse· fetched 2 months ago·verify at source
- 16.0.1.1
- 15.1.2.1
- 14.1.4
- 13.1.3.6
- 12.1.5.3
Official advisory · high-confidence parse· fetched 2 months ago·verify at source
Mitigation
Upgrade to a fixed release: 16.0.1.1, 15.1.2.1, 14.1.4, 13.1.3.6, 12.1.5.3. That is the remediation for this advisory.
The vendor advisory may list additional interim mitigations or workarounds not captured here — review it before change work.
Official advisory · high-confidence parse· fetched 2 months ago·verify at source
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.