CVE-2026-109730 Integer overflow in the Graphics component
An integer overflow in the Graphics component allows attackers to execute arbitrary code, 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-2026-109730?
CVE-2026-109730 is a high-severity vulnerability in Mozilla Firefox, published on 13 Oct 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
Integer overflow in the Graphics component. This vulnerability was fixed in Firefox 158, Firefox ESR 115.43, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
Weakness: CWE-190
Which versions are affected by CVE-2026-109730?
How do I fix CVE-2026-109730?
Upgrade to a fixed version.
Is CVE-2026-109730 being exploited?
There is no known exploitation of CVE-2026-109730 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-109730, GHSA-h2w2-cc3v-p4vg, UBUNTU-CVE-2026-109730.