vulnerability
MFSA2025-30 Firefox: Security Vulnerabilities fixed in Firefox ESR 115.23 (CVE-2025-2817)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 9 | (AV:N/AC:L/Au:S/C:C/I:C/A:C) | Apr 29, 2025 | Apr 30, 2025 | Apr 15, 2026 |
Severity
9
CVSS
(AV:N/AC:L/Au:S/C:C/I:C/A:C)
Published
Apr 29, 2025
Added
Apr 30, 2025
Modified
Apr 15, 2026
Description
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.
Solution
mozilla-firefox-esr-upgrade-115_23
Rapid7 Labs
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