CVE-2021-22991
Actively exploited. CVE-2021-22991 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-01-18) — exploitation has been observed in the wild, and US federal agencies are required to remediate it under BOD 22-01. Treat patching as urgent.
The Traffic Management Microkernel of BIG-IP ASM Risk Engine has a buffer overflow vulnerability, leading to a bypassing of URL-based access controls.
CSIRTS triage
- What
- The Traffic Management Microkernel of BIG-IP ASM Risk Engine has a buffer overflow vulnerability.
- Who is affected
- Deployments of F5 BIG-IP are affected.
- Urgency
- Remediation is urgent as the vulnerability is actively exploited and critical.
- Action
- Apply the latest security updates for F5 BIG-IP.
AI-assisted analysis generated from the source advisory — verify against the original.
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Exploitation outlook
- Exploitation confirmedAlready exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 99% of all EPSS-scored CVEs.
Advisory coverage (1)
- criticalexploitedCVE-2021-22991: F5 BIG-IP Traffic Management Microkernel Buffer Overflowcisa-kev · 2022-01-18
External references
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