Mozjs52: [Unknown description] (CVE-2026-84141)

CVE-2026-84141 is an integer overflow vulnerability affecting the Graphics: ImageLib component in Firefox. It was discovered internally and fixed in Firefox 155 and Firefox ESR 153.2. The vulnerability is part of a broader set of security issues addressed in these releases, some of which showed evidence of memory corruption or other security-relevant defects. The CVSS score is 9.8, indicating high severity, but the vendor advisory classifies the impact of this specific issue as low. No known exploits in the wild have been reported. The vulnerability affects Firefox versions prior to 155 and Firefox ESR versions prior to 153.2.

The vulnerability could potentially lead to memory corruption or other security-relevant defects due to an integer overflow in the Graphics: ImageLib component. However, the vendor advisory categorizes the impact of this specific vulnerability as low. There are no known active exploits in the wild. The overall CVSS score is high (9.8), but this appears to reflect the aggregated severity of multiple vulnerabilities fixed simultaneously rather than this issue alone.

The vulnerability is fixed in Firefox 155 and Firefox ESR 153.2. Users and administrators should update to these versions or later to remediate this issue. No additional mitigation actions are required beyond applying the official updates provided by Mozilla.