CVE-2026-74942

Privilege escalation in the Remote Settings Client component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2056571	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-74/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-75/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-76/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-77/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-78/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-79/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-80/	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mozilla:firefox::::::::
	cpe:2.3:a:mozilla:firefox::::::::
	cpe:2.3:a:mozilla:firefox::::::::
	cpe:2.3:a:mozilla:thunderbird::::::::
	cpe:2.3:a:mozilla:thunderbird::::::::

History

No history.

Information

Published : 2026-08-18 13:17

Updated : 2026-08-21 04:18

NVD link : CVE-2026-74942

Mitre link : CVE-2026-74942

CVE.ORG link : CVE-2026-74942

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-269

Improper Privilege Management

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