UpHeron
All vulnerabilities

Servers and applications

CVE-2025-53521

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.

Actively exploited: CISA added it to its Known Exploited Vulnerabilities catalog on 27 Mar 2026.

Severity
Critical 9.3
Published
15 Oct 2025
Last changed
8 Oct 2026
Added to UpHeron
1 Nov 2026
Fixed in
15.1.10.8, 16.1.6.1, 17.1.3, 17.5.1.3
Sources
NVD

Affected software

SoftwareAffected versions
F5 BIG-IPServers and applications · cpe:a:f5:big-ip_access_policy_manager
  • From 15.1.0 before 15.1.10.8
  • From 16.1.0 before 16.1.6.1
  • From 17.1.0 before 17.1.3
  • From 17.5.0 before 17.5.1.3

Known exploited

CISA name
F5 BIG-IP Stack-Based Buffer Overflow Vulnerability
Required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Due for US agencies
30 Mar 2026
Used in ransomware
Not known

References

  • NVD https://nvd.nist.gov/vuln/detail/CVE-2025-53521
  • CVE.org https://www.cve.org/CVERecord?id=CVE-2025-53521