CVE-2020-5933

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-10-29 · updated 2026-06-17

Description

On versions 15.1.0-15.1.0.5, 14.1.0-14.1.2.3, 13.1.0-13.1.3.4, 12.1.0-12.1.5.1, and 11.6.1-11.6.5.1, when a BIG-IP system that has a virtual server configured with an HTTP compression profile processes compressed HTTP message payloads that require deflation, a Slowloris-style attack can trigger an out-of-memory condition on the BIG-IP system.

Affected products

F5 BIG-IP APM: from 11.6.1 before 11.6.5.2; from 12.1.0 before 12.1.5.2; from 13.1.0 through 13.1.3.4; from 14.1.0 before 14.1.2.4; from 15.1.0 before 15.1.1 — fixed in 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1
BIG-IP: from 11.6.1 before 11.6.5.2; from 12.1.0 before 12.1.5.2; from 13.1.0 through 13.1.3.4; from 14.1.0 before 14.1.2.4; from 15.1.0 before 15.1.1 — fixed in 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1
F5 Big-Ip Analytics: from 11.6.1 before 11.6.5.2; from 12.1.0 before 12.1.5.2; from 13.1.0 through 13.1.3.4; from 14.1.0 before 14.1.2.4; from 15.1.0 before 15.1.1 — fixed in 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1
F5 Networks, Inc. BIG-IP (AAM): from 11.6.1 before 11.6.5.2; from 12.1.0 before 12.1.5.2; from 13.1.0 through 13.1.3.4; from 14.1.0 before 14.1.2.4; from 15.1.0 before 15.1.1 — fixed in 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1
BIG-IP ASM: from 11.6.1 before 11.6.5.2; from 12.1.0 before 12.1.5.2; from 13.1.0 through 13.1.3.4; from 14.1.0 before 14.1.2.4; from 15.1.0 before 15.1.1 — fixed in 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1
F5 BIG-IP DNS: from 11.6.1 before 11.6.5.2; from 12.1.0 before 12.1.5.2; from 13.1.0 through 13.1.3.4; from 14.1.0 before 14.1.2.4; from 15.1.0 before 15.1.1 — fixed in 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1
F5 Big-Ip Fraud Protection Service: from 11.6.1 before 11.6.5.2; from 12.1.0 before 12.1.5.2; from 13.1.0 through 13.1.3.4; from 14.1.0 before 14.1.2.4; from 15.1.0 before 15.1.1 — fixed in 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1
F5 Big-Ip Global Traffic Manager: from 11.6.1 before 11.6.5.2; from 12.1.0 before 12.1.5.2; from 13.1.0 through 13.1.3.4; from 14.1.0 before 14.1.2.4; from 15.1.0 before 15.1.1 — fixed in 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1
F5 Big-Ip Link Controller: from 11.6.1 before 11.6.5.2; from 12.1.0 before 12.1.5.2; from 13.1.0 through 13.1.3.4; from 14.1.0 before 14.1.2.4; from 15.1.0 before 15.1.1 — fixed in 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1
F5 BIG-IP (LTM): from 11.5.2 before 11.6.5.2; from 12.1.0 before 12.1.5.2; from 13.1.0 through 13.1.3.4; from 14.1.0 before 14.1.2.4; from 15.1.0 before 15.1.1 — fixed in 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1
F5 Networks, Inc. BIG-IP (PEM): from 11.6.1 before 11.6.5.2; from 12.1.0 before 12.1.5.2; from 13.1.0 through 13.1.3.4; from 14.1.0 before 14.1.2.4; from 15.1.0 before 15.1.1 — fixed in 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1

How to fix

Upgrade to a fixed version: F5 BIG-IP APM 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1; BIG-IP 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1; F5 Big-Ip Analytics 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1; F5 Networks, Inc. BIG-IP (AAM) 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1; BIG-IP ASM 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1; F5 BIG-IP DNS 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1; F5 Big-Ip Fraud Protection Service 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1; F5 Big-Ip Global Traffic Manager 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1; F5 Big-Ip Link Controller 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1; F5 BIG-IP (LTM) 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1; F5 Networks, Inc. BIG-IP (PEM) 11.6.5.2, 12.1.5.2, 14.1.2.4, 15.1.1. Check the vendor advisory for mitigations.

References

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