CVE-2026-42920: F5 BIG-IP Access Policy Manager

High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 30 days.

When a Client SSL profile is configured with Allow Dynamic Record Sizing on a UDP virtual server, undisclosed traffic 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 Access Policy Manager: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Advanced Firewall Manager: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Advanced Web Application Firewall: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Analytics: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Application Acceleration Manager: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Application Security Manager: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Application Visibility And Reporting: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Automation Toolchain: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Carrier-Grade Nat: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Container Ingress Services: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Ddos Hybrid Defender: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Domain Name System: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Edge Gateway: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Fraud Protection Service: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Global Traffic Manager: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Link Controller: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Local Traffic Manager: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Policy Enforcement Manager: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP SSL Orchestrator: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Webaccelerator: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6
  • F5 BIG-IP Websafe: version 21.0.0 only; from 17.1.0, up to and including 17.1.3; from 17.5.0, up to and including 17.5.1; from 16.1.0, up to and including 16.1.6

Published 2026-05-13. Last modified 2026-06-18.