CVE-2026-16396
Privilege escalation in WebExtensions
CVSS Score
8.8
EPSS Score
0.3%
EPSS Percentile
26th
Privilege escalation in WebExtensions. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.
| Vendor | mozilla |
| Product | firefox |
| Ecosystems | |
| Industries | Technology |
| Published | Jul 21, 2026 |
| Last Updated | Jul 24, 2026 |
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Affected Versions
Mozilla / Firefox
All versions affected Mozilla / Thunderbird
All versions affected References
bugzilla.mozilla.org: https://bugzilla.mozilla.org/show_bug.cgi?id=2047240 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-68/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-70/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-71/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-72/
Credits
Quy Pham