CVE-2026-92045 Sandbox escape due to incorrect boundary conditions in the WebRTC component

Critical 9.6 Published 15 Sep 2026 Updated 21 Sep 2026

Attackers can escape the browser sandbox via incorrect boundary conditions in WebRTC, potentially executing arbitrary code with elevated privileges.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: A user has to click or open something
Fix: Available

What is CVE-2026-92045?

CVE-2026-92045 is a critical memory corruption vulnerability in Mozilla Firefox, published on 15 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

Sandbox escape due to incorrect boundary conditions in the WebRTC component. This vulnerability was fixed in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3.

Weakness: CWE-119

Which versions are affected by CVE-2026-92045?

It affects 2 products.

Products include Mozilla Firefox, Mozilla Thunderbird.

How do I fix CVE-2026-92045?

Upgrade to a fixed version.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2026-92045 being exploited?

There is no known exploitation of CVE-2026-92045 in the wild and no public exploit code.

All Mozilla Firefox vulnerabilities

Sources

Also known as DEBIAN-CVE-2026-92045, GHSA-x4q3-v3jc-6j5v, UBUNTU-CVE-2026-92045.