CVE-2026-74979

Mitigation bypass in the Add-ons Manager component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2045676	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-74/	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/mfsa2026-80/	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mozilla:firefox:::::esr:::*
	cpe:2.3:a:mozilla:firefox:::::-:::*
	cpe:2.3:a:mozilla:thunderbird:::::esr:::*
	cpe:2.3:a:mozilla:thunderbird:::::-:::*

History

No history.

Information

Published : 2026-08-18 13:17

Updated : 2026-08-20 19:51

NVD link : CVE-2026-74979

Mitre link : CVE-2026-74979

CVE.ORG link : CVE-2026-74979

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-284

Improper Access Control

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