CVE-2021-23033: F5 BIG-IP Advanced Web Application Firewall

High severity, CVSS 7.5. EPSS: 0.9% chance of exploitation in the next 30 days.

On BIG-IP Advanced WAF and BIG-IP ASM version 16.x before 16.1.0x, 15.1.x before 15.1.3.1, 14.1.x before 14.1.4.3, 13.1.x before 13.1.4.1, and all versions of 12.1.x, when a WebSocket profile is configured on a virtual server, undisclosed requests can cause bd to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Affected products

• F5 BIG-IP Advanced Web Application Firewall: from 12.1.0, up to and including 12.1.6; from 13.1.0, before 13.1.4.1 (fixed in 13.1.4.1); from 14.1.0, before 14.1.4.3 (fixed in 14.1.4.3); from 15.1.0, before 15.1.3.1 (fixed in 15.1.3.1); from 16.0.0, before 16.1.0 (fixed in 16.1.0)
• F5 BIG-IP Application Security Manager: from 12.1.0, up to and including 12.1.6; from 13.1.0, before 13.1.4.1 (fixed in 13.1.4.1); from 14.1.0, before 14.1.4.3 (fixed in 14.1.4.3); from 15.1.0, before 15.1.3.1 (fixed in 15.1.3.1); from 16.0.0, before 16.1.0 (fixed in 16.1.0)

Published 2021-09-14. Last modified 2026-06-17.