CVE-2026-100792 JIT miscompilation in the JavaScript: WebAssembly component

High 7.1 Published Updated

A JIT miscompilation in the WebAssembly component allows attackers to execute arbitrary code via crafted web content.

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-2026-100792?

CVE-2026-100792 is a high-severity memory corruption vulnerability in Mozilla Firefox, published on 29 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

JIT miscompilation in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.

Weakness: CWE-843

Which versions are affected by CVE-2026-100792?

It affects 2 products.

Products include Mozilla Firefox, Mozilla Thunderbird.

How do I fix CVE-2026-100792?

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-2026-100792 being exploited?

There is no known exploitation of CVE-2026-100792 in the wild and no public exploit code.

All Mozilla Firefox vulnerabilities

Sources

Also known as DEBIAN-CVE-2026-100792, GHSA-m68w-w74f-qp3v, UBUNTU-CVE-2026-100792.

Is CVE-2026-100792 in your software?

Upload an SBOM and sbomify checks it against every vulnerability here, every day.

Check your SBOMs for free