CVE-2020-5926

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-08-26 · updated 2026-06-17
Weakness: CWE-404

Description

In BIG-IP versions 15.1.0-15.1.0.4, 15.0.0-15.0.1.3, and 14.1.0-14.1.2.6, a BIG-IP virtual server with a Session Initiation Protocol (SIP) ALG profile, parsing SIP messages that contain a multi-part MIME payload with certain boundary strings can cause TMM to free memory to the wrong cache.

Affected products

F5 BIG-IP APM: from 14.1.0 before 14.1.2.7; from 15.0.0 before 15.0.1.4; from 15.1.0 before 15.1.0.5 — fixed in 14.1.2.7, 15.0.1.4, 15.1.0.5
BIG-IP: from 14.1.0 before 14.1.2.7; from 15.0.0 before 15.0.1.4; from 15.1.0 before 15.1.0.5 — fixed in 14.1.2.7, 15.0.1.4, 15.1.0.5
F5 Big-Ip Analytics: from 14.1.0 before 14.1.2.7; from 15.0.0 before 15.0.1.4; from 15.1.0 before 15.1.0.5 — fixed in 14.1.2.7, 15.0.1.4, 15.1.0.5
F5 Networks, Inc. BIG-IP (AAM): from 14.1.0 before 14.1.2.7; from 15.0.0 before 15.0.1.4; from 15.1.0 before 15.1.0.5 — fixed in 14.1.2.7, 15.0.1.4, 15.1.0.5
BIG-IP ASM: from 14.1.0 before 14.1.2.7; from 15.0.0 before 15.0.1.4; from 15.1.0 before 15.1.0.5 — fixed in 14.1.2.7, 15.0.1.4, 15.1.0.5
F5 BIG-IP DNS: from 14.1.0 before 14.1.2.7; from 15.0.0 before 15.0.1.4; from 15.1.0 before 15.1.0.5 — fixed in 14.1.2.7, 15.0.1.4, 15.1.0.5
F5 Big-Ip Fraud Protection Service: from 14.1.0 before 14.1.2.7; from 15.0.0 before 15.0.1.4; from 15.1.0 before 15.1.0.5 — fixed in 14.1.2.7, 15.0.1.4, 15.1.0.5
F5 Big-Ip Global Traffic Manager: from 14.1.0 before 14.1.2.7; from 15.0.0 before 15.0.1.4; from 15.1.0 before 15.1.0.5 — fixed in 14.1.2.7, 15.0.1.4, 15.1.0.5
F5 Big-Ip Link Controller: from 14.1.0 before 14.1.2.7; from 15.0.0 before 15.0.1.4; from 15.1.0 before 15.1.0.5 — fixed in 14.1.2.7, 15.0.1.4, 15.1.0.5
F5 BIG-IP (LTM): from 14.1.0 before 14.1.2.7; from 15.0.0 before 15.0.1.4; from 15.1.0 before 15.1.0.5 — fixed in 14.1.2.7, 15.0.1.4, 15.1.0.5
F5 Networks, Inc. BIG-IP (PEM): from 14.1.0 before 14.1.2.7; from 15.0.0 before 15.0.1.4; from 15.1.0 before 15.1.0.5 — fixed in 14.1.2.7, 15.0.1.4, 15.1.0.5

How to fix

Upgrade to a fixed version: F5 BIG-IP APM 14.1.2.7, 15.0.1.4, 15.1.0.5; BIG-IP 14.1.2.7, 15.0.1.4, 15.1.0.5; F5 Big-Ip Analytics 14.1.2.7, 15.0.1.4, 15.1.0.5; F5 Networks, Inc. BIG-IP (AAM) 14.1.2.7, 15.0.1.4, 15.1.0.5; BIG-IP ASM 14.1.2.7, 15.0.1.4, 15.1.0.5; F5 BIG-IP DNS 14.1.2.7, 15.0.1.4, 15.1.0.5; F5 Big-Ip Fraud Protection Service 14.1.2.7, 15.0.1.4, 15.1.0.5; F5 Big-Ip Global Traffic Manager 14.1.2.7, 15.0.1.4, 15.1.0.5; F5 Big-Ip Link Controller 14.1.2.7, 15.0.1.4, 15.1.0.5; F5 BIG-IP (LTM) 14.1.2.7, 15.0.1.4, 15.1.0.5; F5 Networks, Inc. BIG-IP (PEM) 14.1.2.7, 15.0.1.4, 15.1.0.5. Check the vendor advisory for mitigations.

References

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