CVE-2025-6435

8.1 HIGH
Published: June 24, 2025 Modified: November 13, 2025

Description

If a user saved a response from the Network tab in Devtools using the Save As context menu option, that file may not have been saved with the `.download` file extension. This could have led to the user inadvertently running a malicious executable. This vulnerability affects Firefox < 140 and Thunderbird < 140.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1950056
Source: security@mozilla.org
Permissions Required
https://bugzilla.mozilla.org/show_bug.cgi?id=1961777
Source: security@mozilla.org
Permissions Required
https://www.mozilla.org/security/advisories/mfsa2025-51/
Source: security@mozilla.org
Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-54/
Source: security@mozilla.org
Vendor Advisory

4 reference(s) from NVD

Quick Stats

CVSS v3 Score
8.1 / 10.0
EPSS (Exploit Probability)
0.1%
22th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

mozilla