CVE-2025-5266

Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks. This vulnerability affects Firefox < 139, Firefox ESR < 128.11, Thunderbird < 139, and Thunderbird < 128.11.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=1965628	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2025-42/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-44/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-45/
https://www.mozilla.org/security/advisories/mfsa2025-46/

Configurations

Configuration 1 (hide)

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

History

11 Jun 2025, 12:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-05-27 13:15

Updated : 2025-06-11 12:15

NVD link : CVE-2025-5266

Mitre link : CVE-2025-5266

CVE.ORG link : CVE-2025-5266

JSON object : View

Products Affected

mozilla

firefox

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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