Vulnerability · Published Jul 21, 2026 · Assigned by mozilla

CVE-2026-16402Integer overflow in the Graphics: ImageLib component

Critical 9.8

In plain English

A critical-severity integer overflow in Firefox from Mozilla. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 50% of all known vulnerabilities).

Severity (CVSS 3.1)9.8Critical
Exploit odds (30 days)0.6%top 50.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Integer overflow in the Graphics: ImageLib component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Ubuntu:22.04:LTSmozjs102no fix listedUBUNTU-CVE-2026-16402
Ubuntu:24.04:LTSmozjs102no fix listedUBUNTU-CVE-2026-16402
Ubuntu:24.04:LTSmozjs115no fix listedUBUNTU-CVE-2026-16402
Ubuntu:22.04:LTSmozjs78no fix listedUBUNTU-CVE-2026-16402
Ubuntu:22.04:LTSmozjs91no fix listedUBUNTU-CVE-2026-16402
Ubuntu:22.04:LTSthunderbirdno fix listedUBUNTU-CVE-2026-16402

Affected products (as reported)

VendorProductVersions
Mozilla Firefox see references
Mozilla Thunderbird see references

Weakness: CWE-190 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References