PT-2026-40671 · F5 · Big-Ip Next Cnf+3

Published 2026-05-13 · Updated 2026-06-23 · CVE-2026-42409

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions F5 BIG-IP (affected versions not specified) BIG-IP Next SPK (affected versions not specified) BIG-IP Next CNF (affected versions not specified) BIG-IP Next for Kubernetes (affected versions not specified)

Description Undisclosed requests can cause the Traffic Management Microkernel (TMM) process to terminate when an HTTP/2 profile and an iRule containing the 'HTTP::redirect' or 'HTTP::respond' command are configured on a virtual server. This is caused by a null pointer dereference, which occurs when a program attempts to read or write to a memory location that is null.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

NULL Pointer Dereference

Weakness Enumeration

CWE-476

Related Identifiers

CVE-2026-42409

Affected Products

Big-Ip

Big-Ip Next Cnf

Big-Ip Next Spk

Big-Ip Next For Kubernetes

References · 4

• https://nvd.nist.gov/vuln/detail/CVE-2026-42409 · Security Note
• https://my.f5.com/manage/s/article/K000159034 · Vendor Advisory, Patch
• https://t.me/cveNotify/172802 · Telegram Post
• https://twitter.com/f1tym1/status/2056025512955281436 · Twitter Post