CVE-2023-40534: BIG-IP HTTP/2 vulnerability

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-10-10 · updated 2026-06-17
Weakness: CWE-401

Description

When a client-side HTTP/2 profile and the HTTP MRF Router option are enabled for a virtual server, and an iRule using the HTTP_REQUEST event or Local Traffic Policy are associated with the virtual server, undisclosed requests can cause 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 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
BIG-IP: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 Big-Ip Advanced Web Application Firewall: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 Big-Ip Analytics: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 Networks, Inc. BIG-IP (AAM): from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
BIG-IP ASM: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 Big-Ip Application Visibility And Reporting: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 Big-Ip Carrier-Grade Nat: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 Big-Ip Ddos Hybrid Defender: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 BIG-IP DNS: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 Big-Ip Edge Gateway: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 Big-Ip Fraud Protection Service: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 Big-Ip Global Traffic Manager: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 Big-Ip Link Controller: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 BIG-IP (LTM): from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 BIG-IP Next SPK: from 1.6.0 through 1.8.2
F5 Networks, Inc. BIG-IP (PEM): from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 Big-Ip Ssl Orchestrator: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 Big-Ip Webaccelerator: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1
F5 Big-Ip Websafe: from 16.1.0 before 16.1.4.1; 17.1.0 — fixed in 16.1.4.1

How to fix

Upgrade to a fixed version: F5 BIG-IP APM 16.1.4.1; BIG-IP 16.1.4.1; F5 Big-Ip Advanced Web Application Firewall 16.1.4.1; F5 Big-Ip Analytics 16.1.4.1; F5 Networks, Inc. BIG-IP (AAM) 16.1.4.1; BIG-IP ASM 16.1.4.1; F5 Big-Ip Application Visibility And Reporting 16.1.4.1; F5 Big-Ip Carrier-Grade Nat 16.1.4.1; F5 Big-Ip Ddos Hybrid Defender 16.1.4.1; F5 BIG-IP DNS 16.1.4.1; F5 Big-Ip Edge Gateway 16.1.4.1; F5 Big-Ip Fraud Protection Service 16.1.4.1. Check the vendor advisory for mitigations.

References

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