CVE-2026-74963

Same-origin policy bypass in the Networking: Cookies component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2050482	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-74/	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:::::esr:::*
	cpe:2.3:a:mozilla:firefox:::::-:::*
	cpe:2.3:a:mozilla:thunderbird:::::esr:::*
	cpe:2.3:a:mozilla:thunderbird:::::-:::*
	cpe:2.3:a:mozilla:thunderbird:::::esr:::*

History

No history.

Information

Published : 2026-08-18 13:17

Updated : 2026-08-19 01:00

NVD link : CVE-2026-74963

Mitre link : CVE-2026-74963

CVE.ORG link : CVE-2026-74963

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-346

Origin Validation Error

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