CVE-2025-36557: BIG-IP HTTP vulnerability

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-05-07 · updated 2026-06-17
Weakness: CWE-120

Description

When an HTTP profile with the Enforce RFC Compliance option is configured on a virtual server, undisclosed requests can cause the Traffic Management Microkernel (TMM) to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Affected products

F5 BIG-IP APM: from 16.1.0 before 16.1.5; from 17.1.0 before 17.1.2 — fixed in 16.1.5, 17.1.2
BIG-IP: from 16.1.0 before 16.1.5; from 17.1.0 before 17.1.2 — fixed in 16.1.5, 17.1.2
F5 Big-Ip Analytics: from 16.1.0 before 16.1.5; from 17.1.0 before 17.1.2 — fixed in 16.1.5, 17.1.2
F5 Networks, Inc. BIG-IP (AAM): from 16.1.0 before 16.1.5; from 17.1.0 before 17.1.2 — fixed in 16.1.5, 17.1.2
BIG-IP ASM: from 16.1.0 before 16.1.5; from 17.1.0 before 17.1.2 — fixed in 16.1.5, 17.1.2
F5 BIG-IP DNS: from 16.1.0 before 16.1.5; from 17.1.0 before 17.1.2 — fixed in 16.1.5, 17.1.2
F5 Big-Ip Fraud Protection Service: from 16.1.0 before 16.1.5; from 17.1.0 before 17.1.2 — fixed in 16.1.5, 17.1.2
F5 Big-Ip Global Traffic Manager: from 16.1.0 before 16.1.5; from 17.1.0 before 17.1.2 — fixed in 16.1.5, 17.1.2
F5 Big-Ip Link Controller: from 16.1.0 before 16.1.5; from 17.1.0 before 17.1.2 — fixed in 16.1.5, 17.1.2
F5 BIG-IP (LTM): from 16.1.0 before 16.1.5; from 17.1.0 before 17.1.2 — fixed in 16.1.5, 17.1.2
F5 BIG-IP Next CNF: from 1.1.0 before 1.4.0 — fixed in 1.4.0
F5 BIG-IP Next SPK: from 1.7.0 before 1.7.9; from 1.8.0 through 1.9.2 — fixed in 1.7.9
F5 Networks, Inc. BIG-IP (PEM): from 16.1.0 before 16.1.5; from 17.1.0 before 17.1.2 — fixed in 16.1.5, 17.1.2

How to fix

Upgrade to a fixed version: F5 BIG-IP APM 16.1.5, 17.1.2; BIG-IP 16.1.5, 17.1.2; F5 Big-Ip Analytics 16.1.5, 17.1.2; F5 Networks, Inc. BIG-IP (AAM) 16.1.5, 17.1.2; BIG-IP ASM 16.1.5, 17.1.2; F5 BIG-IP DNS 16.1.5, 17.1.2; F5 Big-Ip Fraud Protection Service 16.1.5, 17.1.2; F5 Big-Ip Global Traffic Manager 16.1.5, 17.1.2; F5 Big-Ip Link Controller 16.1.5, 17.1.2; F5 BIG-IP (LTM) 16.1.5, 17.1.2; F5 BIG-IP Next CNF 1.4.0; F5 BIG-IP Next SPK 1.7.9. Check the vendor advisory for mitigations.

References

https://my.f5.com/manage/s/article/K000139571

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