CVE-2021-29951

Mozilla Windows Maintenance Service Weak DACL

Severity Score

6.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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.

El servicio de mantenimiento de Mozilla concedía el acceso de la función SERVICE_START a BUILTIN|Users que, en una red de dominio, concede a usuarios remotos normales el acceso para iniciar o detener el servicio. Esto podría ser usado para impedir que el servicio de actualización del navegador opere (si un atacante enviaba el comando 'Stop'); pero también exponía la superficie de ataque en el servicio de mantenimiento. *Nota: Este problema sólo afecta a los sistemas operativos Windows anteriores a Win 10 build 1709. Los demás sistemas operativos no están afectados. Esta vulnerabilidad afecta a Thunderbird versiones anteriores a 78.10.1, Firefox versiones anteriores a 87 y Firefox ESR versiones anteriores a 78.10.1

Mozilla's Firefox 85 for Windows has a weak DACL for domain networks.

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

Low

Availability

None

Attack Vector

Network

Attack Complexity

Low

Authentication

None

Confidentiality

Partial

Integrity

Partial

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-04-01 CVE Reserved
2021-05-11 CVE Published
2024-03-09 EPSS Updated
2024-08-03 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-269: Improper Privilege Management

CAPEC

References (4)

URL	Tag	Source

URL	Date	SRC

URL	Date	SRC

URL	Date	SRC
https://bugzilla.mozilla.org/show_bug.cgi?id=1690062	2022-07-12
https://www.mozilla.org/security/advisories/mfsa2021-10	2022-07-12
https://www.mozilla.org/security/advisories/mfsa2021-18	2022-07-12
https://www.mozilla.org/security/advisories/mfsa2021-19	2022-07-12

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Mozilla Search vendor "Mozilla"	Firefox Search vendor "Mozilla" for product "Firefox"	< 87.0 Search vendor "Mozilla" for product "Firefox" and version " < 87.0"	-	Affected	in	Microsoft Search vendor "Microsoft"	Windows Search vendor "Microsoft" for product "Windows"	-	-	Safe
Mozilla Search vendor "Mozilla"	Firefox Esr Search vendor "Mozilla" for product "Firefox Esr"	< 78.10.1 Search vendor "Mozilla" for product "Firefox Esr" and version " < 78.10.1"	-	Affected	in	Microsoft Search vendor "Microsoft"	Windows Search vendor "Microsoft" for product "Windows"	-	-	Safe
Mozilla Search vendor "Mozilla"	Thunderbird Search vendor "Mozilla" for product "Thunderbird"	< 78.10.1 Search vendor "Mozilla" for product "Thunderbird" and version " < 78.10.1"	-	Affected	in	Microsoft Search vendor "Microsoft"	Windows Search vendor "Microsoft" for product "Windows"	-	-	Safe