CVE-2026-124903

CRITICAL 9.6

Sandbox escape due to use-after-free in the IPC component

CVSS Score

9.6

EPSS Score

0.0%

EPSS Percentile

0th

Sandbox escape due to use-after-free in the IPC component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.

Vendor	mozilla
Product	firefox
Ecosystems	Browser JavaScript
Industries	Technology
Published	Nov 10, 2026
Last Updated	Nov 10, 2026

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Affected Versions

Mozilla / Firefox

All versions affected

Mozilla / Thunderbird

All versions affected

References

NVD ↗ CVE.org ↗ EPSS Data ↗

bugzilla.mozilla.org: https://bugzilla.mozilla.org/show_bug.cgi?id=2084673 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-125/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-126/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-127/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-128/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-129/

Credits

Mozilla