CVE-2026-12304
Received Received - Intake
Same-Origin Policy Bypass in Firefox

Publication date: 2026-06-16

Last updated on: 2026-06-16

Assigner: Mozilla Corporation

Description
Same-origin policy bypass in the Networking: Cookies component. This vulnerability was fixed in Firefox 152 and Firefox ESR 140.12.
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Meta Information
Published
2026-06-16
Last Modified
2026-06-16
Generated
2026-06-16
AI Q&A
2026-06-16
EPSS Evaluated
N/A
NVD
CVE-2026-12304
EUVD
EUVD-2026-37095
Affected Vendors & Products
Showing 2 associated CPEs
Vendor Product Version / Range
mozilla firefox 152
mozilla firefox_esr 140.12
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Exploitability
CWE
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KEV
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CWE ID Description
CWE-UNKNOWN
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Executive Summary

This vulnerability is a same-origin policy bypass in the Networking: Cookies component of Mozilla Firefox. The same-origin policy is a critical security mechanism that restricts how documents or scripts loaded from one origin can interact with resources from another origin. A bypass of this policy could allow unauthorized access to cookies across different origins.

The issue was addressed and fixed in Firefox version 152 and Firefox ESR 140.12.

Impact Analysis

By bypassing the same-origin policy in the cookies component, an attacker could potentially access or manipulate cookies from other origins without proper authorization. This could lead to unauthorized access to user sessions, personal data, or other sensitive information stored in cookies.

Mitigation Strategies

To mitigate this vulnerability, update Firefox to version 152 or later, or Firefox ESR to version 140.12 or later, where the issue has been fixed.

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