CVE-2025-1012
Use-after-free during concurrent delazification
CVSS Score
9.8
EPSS Score
0.0%
EPSS Percentile
0th
A race during concurrent delazification could have led to a use-after-free. This vulnerability was fixed in Firefox 135, Firefox ESR 115.20, Firefox ESR 128.7, Thunderbird 128.7, and Thunderbird 135.
| Vendor | mozilla |
| Product | firefox |
| Ecosystems | |
| Industries | Technology |
| Published | Feb 4, 2025 |
| Last Updated | Apr 13, 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=1939710 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2025-07/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2025-08/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2025-09/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2025-10/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2025-11/ lists.debian.org: https://lists.debian.org/debian-lts-announce/2025/02/msg00006.html lists.debian.org: https://lists.debian.org/debian-lts-announce/2025/02/msg00005.html
Credits
Nils Bars