CVE-2020-15663
Mozilla: Downgrade attack on the Mozilla Maintenance Service could have resulted in escalation of privilege
Severity
ImportantRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · August 25, 2020
Updated · November 21, 2025
Description
If Firefox is installed to a user-writable directory, the Mozilla Maintenance Service would execute updater.exe from the install location with system privileges. Although the Mozilla Maintenance Service does ensure that updater.exe is signed by Mozilla, the version could have been rolled back to a previous version which would have allowed exploitation of an older bug and arbitrary code execution with System Privileges. Note: This issue only affected Windows operating systems. Other operating systems are unaffected.. This vulnerability affects Firefox < 80, Thunderbird < 78.2, Thunderbird < 68.12, Firefox ESR < 68.12, and Firefox ESR < 78.2.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 8.8CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE-282 · Improper Ownership Management