CVE-2021-22991Actively exploitedAdded to KEV 2022-01-18

F5 BIG-IP Traffic Management Microkernel Buffer Overflow

F5, BIG-IP Traffic Management Microkernel

Description

The Traffic Management Microkernel of BIG-IP ASM Risk Engine has a buffer overflow vulnerability, leading to a bypassing of URL-based access controls.

CVSS severity for this advisory hasn't been enriched from NVD yet, check back shortly.

EPSS, exploit probability

Critical

62.4%

estimated chance of real-world exploitation in the next 30 days, higher than 99.2% of every CVE FIRST.org scores

Refreshed 10/28/2026, via FIRST.org's EPSS model, not CVSS, this measures likelihood of exploitation, not how severe it would be.

Required action

Apply updates per vendor instructions.

CISA-recommended due date: 2022-02-01

CWE-119

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