CVE-2026-2785 Invalid pointer in the JavaScript Engine component

High 8.8 Published Updated

An invalid pointer in the JavaScript Engine can cause a crash, requiring users to upgrade Firefox and Thunderbird.

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-2026-2785?

CVE-2026-2785 is a high-severity vulnerability in Mozilla Firefox, published on 24 Feb 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

Invalid pointer in the JavaScript Engine component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

Weakness: CWE-824

Which versions are affected by CVE-2026-2785?

It affects 2 products.

Products include Mozilla Firefox, Mozilla Thunderbird.

How do I fix CVE-2026-2785?

Upgrade to a fixed version.

Is CVE-2026-2785 being exploited?

There is no known exploitation of CVE-2026-2785 in the wild and no public exploit code.

All Mozilla Firefox vulnerabilities

Sources

Also known as DEBIAN-CVE-2026-2785, GHSA-3px2-2xc4-mxr2, UBUNTU-CVE-2026-2785.

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