CVE-2026-0877

Mitigation bypass in the DOM: Security component. This vulnerability affects Firefox < 147, Firefox ESR < 115.32, Firefox ESR < 140.7, Thunderbird < 147, and Thunderbird < 140.7.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=1999257	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-01/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-02/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-03/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-04/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-05/	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:firefox:::::esr:::*
	cpe:2.3:a:mozilla:thunderbird:::::esr:::*
	cpe:2.3:a:mozilla:thunderbird:::::-:::*

History

No history.

Information

Published : 2026-01-13 14:16

Updated : 2026-01-22 18:52

NVD link : CVE-2026-0877

Mitre link : CVE-2026-0877

CVE.ORG link : CVE-2026-0877

JSON object : View

Products Affected

mozilla

firefox
thunderbird

CWE

CWE-693

Protection Mechanism Failure

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