The Firefox updater created a directory writable by non-privileged users. When uninstalling Firefox, any files in that directory would be recursively deleted with the permissions of the uninstalling user account. This could be combined with creation of a junction (a form of symbolic link) to allow arbitrary file deletion controlled by the non-privileged user. *This bug only affects Firefox on Windows. Other operating systems are unaffected.* This vulnerability affects Firefox < 116, Firefox ESR < 115.1, and Thunderbird < 115.1.
Fix
Patch, vendor advisory and mitigation references on NVD 4
- https://www.mozilla.org/security/advisories/mfsa2023-29/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2023-31/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2023-29/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2023-31/ Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 6.5 · mozillaNVD modified 2026-10-23 23:10
Affected (CPE criteria) 2
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*
References 8
- https://bugzilla.mozilla.org/show_bug.cgi?id=1824420 Issue Tracking, Permissions Required
- https://www.mozilla.org/security/advisories/mfsa2023-29/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2023-31/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2023-33/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1824420 Issue Tracking, Permissions Required
- https://www.mozilla.org/security/advisories/mfsa2023-29/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2023-31/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2023-33/