CVE-2025-4086

A specially crafted filename containing a large number of encoded newline characters could obscure the file's extension when displayed in the download dialog. *This bug only affects Thunderbird for Android. Other versions of Thunderbird are unaffected.*. This vulnerability was fixed in Firefox 138 and Thunderbird 138.

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=1945705	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2025-28/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-31/	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2025-04-29 14:15

Updated : 2026-06-17 09:32

NVD link : CVE-2025-4086

Mitre link : CVE-2025-4086

CVE.ORG link : CVE-2025-4086

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-451

User Interface (UI) Misrepresentation of Critical Information

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