CVE-2026-8960

Spoofing issue in WebExtensions. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=1940116	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-46/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-50/	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-05-19 14:16

Updated : 2026-06-17 11:04

NVD link : CVE-2026-8960

Mitre link : CVE-2026-8960

CVE.ORG link : CVE-2026-8960

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-290

Authentication Bypass by Spoofing

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