CVE-2023-29532: Mozilla Firefox

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

A local attacker can trick the Mozilla Maintenance Service into applying an unsigned update file by pointing the service at an update file on a malicious SMB server. The update file can be replaced after the signature check, before the use, because the write-lock requested by the service does not work on a SMB server. *Note: This attack requires local system access and only affects Windows. Other operating systems are not affected.* This vulnerability affects Firefox < 112, Firefox ESR < 102.10, and Thunderbird < 102.10.

Affected products

• Mozilla Firefox: before 112.0 (fixed in 112.0)
• Mozilla Firefox ESR: before 102.10 (fixed in 102.10)
• Mozilla Thunderbird: before 102.10 (fixed in 102.10)

Published 2023-06-19. Last modified 2026-06-17.