CVE-2021-33796 Use after free in MuJS

Critical 10.0 Published 7 Jul 2023 Updated 12 Nov 2024

A use-after-free flaw in MuJS allows attackers to cause a denial of service via regexp source property access.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2021-33796?

CVE-2021-33796 is a critical use after free vulnerability in MuJS, published on 7 Jul 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

In MuJS before version 1.1.2, a use-after-free flaw in the regexp source property access may cause denial of service.

Weakness: CWE-416

Which versions are affected by CVE-2021-33796?

It affects 1 product.

Products include Artifex Mujs.

How do I fix CVE-2021-33796?

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-2021-33796 being exploited?

There is no known exploitation of CVE-2021-33796 in the wild and no public exploit code.

Sources

Also known as DEBIAN-CVE-2021-33796, GHSA-pc6c-fw6q-cfhj.