CVE-2021-29951
Published: 24 June 2021
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.*. This vulnerability affects Thunderbird < 78.10.1, Firefox < 87, and Firefox ESR < 78.10.1.
Notes
| Author | Note |
|---|---|
| alexmurray | Only affects Firefox on Windows, does not affect Firefox on Ubuntu |
Priority
Status
| Package | Release | Status |
|---|---|---|
|
firefox Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(code not present)
|
| focal |
Not vulnerable
(code not present)
|
|
| groovy |
Not vulnerable
(code not present)
|
|
| hirsute |
Not vulnerable
(code not present)
|
|
| trusty |
Does not exist
|
|
| upstream |
Not vulnerable
(debian: Only affects Windows)
|
|
| xenial |
Ignored
(end of standard support)
|
|
|
firefox-esr Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| hirsute |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Not vulnerable
(debian: Only affects Windows)
|
|
| xenial |
Ignored
(end of standard support)
|
|
|
thunderbird Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(code not present)
|
| focal |
Not vulnerable
(code not present)
|
|
| groovy |
Not vulnerable
(code not present)
|
|
| hirsute |
Not vulnerable
(code not present)
|
|
| trusty |
Does not exist
|
|
| upstream |
Not vulnerable
(debian: Only affects Windows)
|
|
| xenial |
Ignored
(end of standard support)
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 6.5 |
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | Low |
| Integrity impact | Low |
| Availability impact | None |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |