CVE-2026-89161 Use after free in PCRE2

High 7.4 Published 11 Sep 2026 Updated 11 Sep 2026

A use-after-free vulnerability in PCRE2 allows attackers to execute arbitrary code or cause denial of service via crafted regex patterns.

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-2026-89161?

CVE-2026-89161 is a high-severity use after free vulnerability in PCRE2, published on 11 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In PCRE2 before 10.48, pcre2_jit_match mishandles a previously copied subject being passed in as a context. An incorrect free operation can occur.

Weakness: CWE-590

Which versions are affected by CVE-2026-89161?

It affects 1 product.

Products include Pcre Pcre2.

How do I fix CVE-2026-89161?

Upgrade to a fixed version.

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-2026-89161 being exploited?

There is no known exploitation of CVE-2026-89161 in the wild and no public exploit code.

Sources

Also known as ALPINE-CVE-2026-89161, AZL-100053, AZL-101766, AZL-101790, AZL-101802, AZL-101823 and 7 more.