The Firefox updater created a directory writable by non-privileged users....

Vulnerability Description

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.

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=1824420
• https://www.mozilla.org/security/advisories/mfsa2023-29/
• https://www.mozilla.org/security/advisories/mfsa2023-31/
• https://www.mozilla.org/security/advisories/mfsa2023-33/