CVE-2025-6430

When a file download is specified via the `Content-Disposition` header, that directive would be ignored if the file was included via a `<embed>` or `<object>` tag, potentially making a website vulnerable to a cross-site scripting attack. This vulnerability was fixed in Firefox 140, Firefox ESR 128.12, Thunderbird 140, and Thunderbird 128.12.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=1971140	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2025-51/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-53/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-54/
https://www.mozilla.org/security/advisories/mfsa2025-55/
https://lists.debian.org/debian-lts-announce/2025/06/msg00029.html
https://lists.debian.org/debian-lts-announce/2025/07/msg00002.html

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2025-06-24 13:15

Updated : 2026-06-17 10:01

NVD link : CVE-2025-6430

Mitre link : CVE-2025-6430

CVE.ORG link : CVE-2025-6430

JSON object : View

Products Affected

mozilla

firefox

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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