CVE-2025-2817
Privilege escalation in Thunderbird Updater
CVSS Score
8.8
EPSS Score
0.0%
EPSS Percentile
0th
Thunderbird's update mechanism allowed a medium-integrity user process to interfere with the SYSTEM-level updater by manipulating the file-locking behavior. By injecting code into the user-privileged process, an attacker could bypass intended access controls, allowing SYSTEM-level file operations on paths controlled by a non-privileged user and enabling privilege escalation. This vulnerability was fixed in Firefox 138, Firefox ESR 128.10, Firefox ESR 115.23, Thunderbird 138, and Thunderbird 128.10.
| Vendor | mozilla |
| Product | firefox |
| Ecosystems | |
| Industries | Technology |
| Published | Apr 29, 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=1917536 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2025-28/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2025-29/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2025-30/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2025-31/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2025-32/ lists.debian.org: https://lists.debian.org/debian-lts-announce/2025/05/msg00022.html
Credits
Dong-uk Kim (@justlikebono)