CVE-2026-84120
Use-after-free in the Audio/Video component
CVSS Score
5.4
EPSS Score
0.0%
EPSS Percentile
0th
Use-after-free in the Audio/Video component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
| Vendor | mozilla |
| Product | firefox |
| Ecosystems | |
| Industries | Technology |
| Published | Sep 1, 2026 |
| Last Updated | Sep 1, 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=2058911 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-82/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-83/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-84/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-85/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-86/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-87/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-88/
Credits
Ukyo Akai