CVE-2025-53521 — F5 BIG-IP Stack-Based Buffer Overflow Vulnerability
CVE-2025-53521: F5 BIG-IP Stack-Based Buffer Overflow Vulnerability
CISA Known Exploited Vulnerability (KEV)
| Vendor / project | F5 |
| Product | BIG-IP |
| Date added | 2026-03-27 |
| Due date | 2026-03-30 |
| Ransomware campaign use | Unknown |
Description
F5 BIG-IP APM contains a stack-based buffer overflow vulnerability that could allow a threat actor to achieve remote code execution.
Required action (CISA)
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Notes
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
References
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-53521
- KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog