CVE-2026-40467 Use after free in gawk

Medium 5.1 Published 13 Jul 2026 Updated 13 Jul 2026

A use-after-free flaw in gawk allows attackers to cause a crash via the do_getline_redir routine, impacting system stability.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2026-40467?

CVE-2026-40467 is a medium-severity use after free vulnerability in GNU gawk, published on 13 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Use After Free vulnerability has been found in "io.c" program file of gawk (do_getline_redir() routine). This issue may lead to a crash. It affects gawk in versions 5.4.0 and below.

Weakness: CWE-416

Which versions are affected by CVE-2026-40467?

It affects 1 product.

Products include Fossies Gawk.

How do I fix CVE-2026-40467?

Apply the vendor's patch.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2026-40467 being exploited?

There is no known exploitation of CVE-2026-40467 in the wild and no public exploit code.

Sources

Also known as AZL-92292, BELL-CVE-2026-40467, DEBIAN-CVE-2026-40467, ECHO-d087-e069-12ce, GHSA-wj49-xjpv-3f4m, JLSEC-2026-785 and 1 more.