MSRXVulnerabilities / CVE-2025-53521
CVE-2025-53521
Published 2025-10-15 · Analyzed
CVE-2025-53521
F5 BIG-IP Stack-Based Buffer Overflow Vulnerability
Exploited in the wild: CISA added it to the Known Exploited Vulnerabilities catalog on 2026-03-27, with a fix-by date of 2026-03-30. Patch it first.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
9.3 CRITICAL
CVSS 4.0 · CNA · f5.com
CVSS 4.0 · CNA · f5.com
2.3%
chance of exploitation in the next 30 days (EPSS; higher than 83% of CVEs)
chance of exploitation in the next 30 days (EPSS; higher than 83% of CVEs)
When a BIG-IP APM access policy is configured on a virtual server, specific malicious traffic can lead to Remote Code Execution (RCE). Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Scores
Affected products
- f5 big-ip access policy manager: ≥ 15.1.0, < 15.1.10.8; ≥ 16.1.0, < 16.1.6.1; ≥ 17.1.0, < 17.1.3; ≥ 17.5.0, < 17.5.1.3
Weakness: CWE-121
2 references (advisories, patches, write-ups)
- https://my.f5.com/manage/s/article/K000156741 · Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-53521 · US Government Resource
Sources: NVD, CVE.org, FIRST EPSS. Missing ones did not answer or have no record yet.