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

30 Sep 2026, 18:10

Type	Values Removed	Values Added
Summary	(es) Un nombre de archivo especialmente manipulado que contiene una gran cantidad de caracteres de nueva línea codificados podría ocultar la extensión del archivo al mostrarse en el cuadro de diálogo de descarga. Este error solo afecta a Firefox para Android. Las demás versiones de Firefox no se ven afectadas. Esta vulnerabilidad afecta a Firefox (versión anterior a la 138) y Thunderbird (versión anterior a la 138).	(es) Un nombre de archivo especialmente manipulado que contiene una gran cantidad de caracteres de nueva línea codificados podría ocultar la extensión del archivo al mostrarse en el cuadro de diálogo de descarga. Este error solo afecta a Firefox para Android. Las demás versiones de Firefox no se ven afectadas.* Esta vulnerabilidad afecta a Firefox (versión anterior a la 138) y Thunderbird (versión anterior a la 138).

Information

Published : 2025-04-29 14:15

Updated : 2026-09-30 18:10

NVD link : CVE-2025-4086

Mitre link : CVE-2025-4086

CVE.ORG link : CVE-2025-4086

JSON object : View

Products Affected

mozilla

firefox
thunderbird

CWE

CWE-451

User Interface (UI) Misrepresentation of Critical Information

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