CISA Known Exploited Vulnerability
This vulnerability is actively exploited in the wild and listed in the CISA Known Exploited Vulnerabilities catalog.
Remediation Deadline: Mar 30, 2026
Description
F5 BIG-IP APM contains an unspecified vulnerability that could allow a threat actor to achieve remote code execution.
EPSS — Exploit Probability
Higher than 95.3% of all CVEs
Required Action
Please adhere to F5’s guidelines to assess exposure and mitigate risks. Check for signs of potential compromise on all internet accessible F5 products affected by this vulnerability. For more information please see: https://my.f5.com/manage/s/article/K000156741 ; https://my.f5.com/manage/s/article/K000160486 ; https://my.f5.com/manage/s/article/K11438344 ; https://nvd.nist.gov/vuln/detail/CVE-2025-53521
Related Articles (2)
CISA Adds One Known Exploited Vulnerability to Catalog
CISA has added one new vulnerability to its Known Exploited Vulnerabilities (KEV) Catalog, based on evidence of active exploitation.
Mar 27, 2026
CISA Adds CVE-2025-53521 to KEV After Active F5 BIG-IP APM Exploitation
CISA adds actively exploited F5 BIG-IP APM CVE-2025-53521 (CVSS 9.3) to KEV, ordering FCEB patch by March 30, 2026 to curb RCE risk.
Mar 28, 2026
Risk Assessment
ELEVATEDDetails
- Severity
- High
- EPSS
- 19.2%
- CISA KEV
- Yes
- Ransomware
- Unknown
- Articles
- 2
Timeline
Published
Mar 27, 2026
Added to KEV
Mar 27, 2026
Remediation Due
Mar 30, 2026