CriticalCritical vulnerability

CVE-2026-100819 (CVSS 9.6)

NVD · officialPublished Sep 29, 2026Risk 50/100

Sandbox escape due to incorrect boundary conditions in the XPCOM component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.

Technical details

CVSS

9.6

AV:NetworkAC:LowPR:NoneUI:RequiredC:HighI:HighA:High

Evidence and sources

This record is attributed to NVD. Exploitation status and remediation guidance are kept separate from the vulnerability's technical severity.

Open primary source