CVE-2025-5266

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

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

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/
https://lists.debian.org/debian-lts-announce/2025/05/msg00043.html
https://lists.debian.org/debian-lts-announce/2025/05/msg00046.html

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2025-05-27 13:15

Updated : 2026-06-17 09:47

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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