CVE-2025-53521: F5 BIG-IP Unspecified Vulnerability

Published Oct 15, 2025
·
Updated

F5 BIG-IP APM contains a stack-based buffer overflow vulnerability that could allow a threat actor to achieve remote code execution.

Other sources

When a BIG-IP APM access policy is configured on a virtual server, specific malicious traffic can lead to Remote Code Execution (RCE).

F5

Affected Software

8 affected componentsFixes available
F5 BIG-IP
F5 BIG-IP APM>=17.5.0<=17.5.1, >=17.1.0<=17.1.2
17.5.1.317.1.3
F5 BIG-IP APM>=16.1.0<=16.1.6
16.1.6.1
F5 BIG-IP APM>=15.1.0<=15.1.10
15.1.10.8
F5 BIG-IP Access Policy Manager>=15.1.0<15.1.10.8
F5 BIG-IP Access Policy Manager>=16.1.0<16.1.6.1
F5 BIG-IP Access Policy Manager>=17.1.0<17.1.3
F5 BIG-IP Access Policy Manager>=17.5.0<17.5.1.3

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 17.5.1.317.1.3
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 16.1.6.1
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 15.1.10.8
  4. Upgrade

    Upgrade F5 BIG-IP APM to a version that resolves this vulnerability.

    Fixed in 15.1.10.8
  5. Upgrade

    Upgrade F5 BIG-IP APM to a version that resolves this vulnerability.

    Fixed in 16.1.6.1
  6. Upgrade

    Upgrade F5 BIG-IP APM to a version that resolves this vulnerability.

    Fixed in 17.5.1.317.1.3
  7. Compensating control

    Follow applicable BOD 22-01 guidance for cloud services and discontinue use of F5 BIG-IP APM if vendor mitigations are unavailable; apply any vendor-provided mitigations for F5 BIG-IP APM until the listed fixed versions can be deployed.

Event History

Oct 15, 2025
Advisory Published
via F5·11:01 AM
Data Sourced
via F5·11:01 AM
DescriptionSeverityWeaknessAffected Software
CVE Published
via MITRE·01:55 PM
Data Sourced
via MITRE·01:55 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·02:15 PM
DescriptionSeverityWeaknessAffected Software
Mar 27, 2026
Known Exploited
via CISA·12:00 AM
Data Sourced
via CISA·12:00 AM
RemedyDescriptionAffected Software
Mar 30, 2026
News Published
via BleepingComputer·10:59 AM
News Published
via BleepingComputer·11:00 AM
Apr 2, 2026
News Published
via BleepingComputer·08:25 AM
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Frequently Asked Questions

1

What is the severity of CVE-2025-53521?

CVE-2025-53521 is considered a high severity vulnerability due to its potential to terminate the Traffic Management Microkernel.

2

How do I fix CVE-2025-53521?

To fix CVE-2025-53521, you should update F5 BIG-IP APM to the latest patched version according to the vendor's advisory.

3

Which versions of BIG-IP APM are affected by CVE-2025-53521?

CVE-2025-53521 affects F5 BIG-IP APM versions 15.1.0 to 15.1.10, 16.1.0 to 16.1.6, and 17.1.0 to 17.5.1.

4

Does CVE-2025-53521 impact performance?

Yes, CVE-2025-53521 can impact performance by causing the Traffic Management Microkernel to unexpectedly terminate.

5

What are the potential consequences of CVE-2025-53521?

The potential consequences of CVE-2025-53521 include service disruptions and security risks due to the termination of network traffic management.

Contact

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