Is It On KEV?

F5 BIG-IP

YES - ON THE CISA KEV LIST
CVE-2025-53521

F5 BIG-IP Stack-Based Buffer Overflow Vulnerability

CISA catalog due date2026-03-30
226 days past due
EPSS exploit probability (next 30 days)2.3% · 83percentile
From CVE publication to KEV listing163 days (2025-10-15 → 2026-03-27)
Remediation window (KEV listing to due date)3 days
Days on the KEV list229 days
Date added to KEV2026-03-27
Known ransomware campaign useUnknown
VendorF5
ProductBIG-IP
Weaknesses (CWE)CWE-121

F5: 8 entries (0.4% of all KEV entries are from this vendor); 2 added in 2026.

BOD 26-04 note: this is the date printed in the CISA catalog. A federal agency's actual deadline is set by its SSVC tier - Act (3 days), Attend (14 days), Track (60 days), or the next scheduled upgrade - counted from the KEV listing date or the date the vulnerability is identified in its environment, whichever comes first. Use the tier helper on each CVE page for your own window.

Your BOD 26-04 window (SSVC tier helper)

Your remediation window ends:

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

Other KEV entries for this vendor: F5

F5 - Vendors with KEV entries

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