CVE-2026-100824 Privilege escalation in the Places component

High 8.8 Published 29 Sep 2026 Updated 30 Sep 2026

An attacker can escalate privileges via the Places component in Mozilla Firefox and Thunderbird, requiring users to update to the latest versions.

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-2026-100824?

CVE-2026-100824 is a high-severity 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

Privilege escalation in the Places component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.

Weakness: CWE-269

Which versions are affected by CVE-2026-100824?

It affects 2 products.

Products include Mozilla Firefox, Mozilla Thunderbird.

How do I fix CVE-2026-100824?

Upgrade to a fixed version.

Is CVE-2026-100824 being exploited?

There is no known exploitation of CVE-2026-100824 in the wild and no public exploit code.

All Mozilla Firefox vulnerabilities

Sources

Also known as DEBIAN-CVE-2026-100824, GHSA-9q9m-5pqf-q3gj, UBUNTU-CVE-2026-100824.