CVE-2026-8401

Sandbox escape in the Profile Backup component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, Firefox ESR 140.11, and Thunderbird 140.11.

CVSS 3.1

9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

0.3% chance of exploitation in the next 30 days; higher than 24% of CVEs (scores of 2026-10-26)

CWEs

CWE-693, CWE-653

Published

2026-05-12

Modified

2026-10-26

Record from

the NVD, synced 2026-10-26

Affected

• mozilla:firefox

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=2038679
• https://www.mozilla.org/security/advisories/mfsa2026-45/
• https://www.mozilla.org/security/advisories/mfsa2026-47/
• https://www.mozilla.org/security/advisories/mfsa2026-48/
• https://www.mozilla.org/security/advisories/mfsa2026-51/

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