UpHeron
All vulnerabilities

Servers and applications

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 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…

Actively exploited: CISA added it to its Known Exploited Vulnerabilities catalog on 18 Jan 2022.

Severity
Critical 9.8
Published
31 Mar 2021
Last changed
17 Jun 2026
Added to UpHeron
1 Nov 2026
Fixed in
12.1.5.3, 13.1.3.6, 14.1.4, 15.1.2.1, 16.0.1.1
Sources
NVD

Affected software

SoftwareAffected versions
F5 BIG-IPServers and applications · cpe:a:f5:big-ip_access_policy_manager
  • From 12.1.0 before 12.1.5.3
  • From 13.1.0 before 13.1.3.6
  • From 14.1.0 before 14.1.4
  • From 15.1.0 before 15.1.2.1
  • From 16.0.0 before 16.0.1.1
F5 BIG-IPServers and applications · cpe:a:f5:big-ip_local_traffic_manager
  • From 12.1.0 before 12.1.5.3
  • From 13.1.0 before 13.1.3.6
  • From 14.1.0 before 14.1.4
  • From 15.1.0 before 15.1.2.1
  • From 16.0.0 before 16.0.1.1

Known exploited

CISA name
F5 BIG-IP Traffic Management Microkernel Buffer Overflow
Required action
Apply updates per vendor instructions.
Due for US agencies
1 Feb 2022
Used in ransomware
Not known

References

  • NVD https://nvd.nist.gov/vuln/detail/CVE-2021-22991
  • CVE.org https://www.cve.org/CVERecord?id=CVE-2021-22991