CVE-2026-12325 Denial-of-service in the Graphics: ImageLib component
An attacker can cause a denial of service in Firefox and Thunderbird via the Graphics ImageLib component, requiring users to upgrade to patched 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-2026-12325?
CVE-2026-12325 is a medium-severity denial of service vulnerability in Mozilla Firefox, published on 16 Jun 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
Denial-of-service in the Graphics: ImageLib component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.
Weakness: CWE-400
Which versions are affected by CVE-2026-12325?
It affects 2 products.
Products include Mozilla Firefox, Mozilla Thunderbird.
How do I fix CVE-2026-12325?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-12325 being exploited?
There is no known exploitation of CVE-2026-12325 in the wild and no public exploit code.
Other vulnerabilities in Mozilla Firefox
Sources
Also known as DEBIAN-CVE-2026-12325, GHSA-w26x-6wxp-828q, UBUNTU-CVE-2026-12325.