CVE-2026-6771

Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.

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=2025067	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-30/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-32/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-33/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-34/	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-04-21 13:16

Updated : 2026-06-17 11:01

NVD link : CVE-2026-6771

Mitre link : CVE-2026-6771

CVE.ORG link : CVE-2026-6771

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-288

Authentication Bypass Using an Alternate Path or Channel

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