CVE-2025-54858 BIG-IP Advanced WAF and ASM vulnerability

High 8.7 Published 15 Oct 2025 Updated 26 Feb 2026

Attackers can cause a denial of service by sending specific requests to a BIG-IP virtual server configured with a malformed JSON schema in a WAF or ASM policy.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2025-54858?

CVE-2025-54858 is a high-severity denial of service vulnerability in F5 Big-Ip Advanced Web Application Firewall, published on 15 Oct 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

When a BIG-IP Advanced WAF or BIG-IP ASM Security Policy is configured with a JSON content profile that has a malformed JSON schema, and the security policy is applied to a virtual server, undisclosed requests can cause the bd process to terminate.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Weakness: CWE-674

Which versions are affected by CVE-2025-54858?

It affects 2 products.

Products include F5 Big-Ip Advanced Web Application Firewall, F5 Big-Ip Application Security Manager.

How do I fix CVE-2025-54858?

No fix has been published for CVE-2025-54858 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2025-54858 being exploited?

There is no known exploitation of CVE-2025-54858 in the wild and no public exploit code.

All F5 Big-Ip Advanced Web Application Firewall vulnerabilities

Sources

Also known as GHSA-g256-87j3-gw89.