CVE-2021-22991
BIG-IP
Published 31 Mar 2021 · updated 17 Jun 2026 · Analyzed
Exploited in the wild
CISA added this to its Known Exploited Vulnerabilities catalog on 18 Jan 2022, with a remediation deadline of 1 Feb 2022 for US federal agencies.
Required action: Apply updates per vendor instructions.
Description
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.
References
- support.f5.com/csp/article/K56715231 · Vendor Advisory
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-22991 · US Government Resource