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Mozilla Foundation Security Advisory 2021-18

Security Vulnerabilities fixed in Firefox ESR 78.10.1

Announced
May 4, 2021
Impact
moderate
Products
Firefox ESR
Fixed in
  • Firefox ESR 78.10.1

#CVE-2021-29951: Mozilla Maintenance Service could have been started or stopped by domain users

Reporter
James Forshaw
Impact
moderate
Description

The Mozilla Maintenance Service granted SERVICE_START access to BUILTIN|Users which, in a domain network, grants normal remote users access to start or stop the service. This could be used to prevent the browser update service from operating (if an attacker spammed the 'Stop' command); but also exposed attack surface in the maintenance service.
Note: This issue only affected Windows operating systems older than Win 10 build 1709. Other operating systems are unaffected.

References