CVE-2025-53521

CRITICAL CISA KEV EPSS 80.7%
Published Oct 15, 20258mo ago · Modified Jun 17, 20262w ago
9.3 CVSS 4.0
Critical
Find Similar
Published Oct 15, 2025 8mo ago
Last Modified Jun 17, 2026 2w ago
KEV Listed Mar 27, 2026 3mo ago
KEV Due Mar 30, 2026 93d overdue

Description

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.

CVSS Details

Base Score
9.3
Exploitability
—
Impact
—
Vector string
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X

Threat Intelligence

CISA Known Exploited Overdue 93d
Added
Mar 27, 2026
Due
Mar 30, 2026

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

EPSS Exploit Probability
80.7% percentile
Exploit & Patch Status
Actively Exploited (KEV)
No Patch Available

Weaknesses 1

CWE-121

Affected Products 4

VendorProductVersionRange
f5big-ip_access_policy_manager*≥15.1.0  –  <15.1.10.8
f5big-ip_access_policy_manager*≥16.1.0  –  <16.1.6.1
f5big-ip_access_policy_manager*≥17.1.0  –  <17.1.3
f5big-ip_access_policy_manager*≥17.5.0  –  <17.5.1.3

References 2

  • my.f5.com https://my.f5.com/manage/s/article/K000156741
    Vendor Advisory
  • cisa.gov https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-53521
    US Government Resource

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.