CVE-2025-4086 - CVE House
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Status published Unknown CVE-2025-4086

Specially crafted filename could be used to obscure download type

Vulnerability Description

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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • Hafiizh

References

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Affected Vendor

Affected Software

Firefox, Thunderbird
Vulnerable Versions:
138

Timeline

Official Publish: April 29th, 2025
Last Modified: April 13th, 2026
Added to House: July 22nd, 2026

CVSS Vectors

No vector data available

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.