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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2025-6435 Detail

Current 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 was fixed in Firefox 140 and Thunderbird 140.


View Analysis Description

Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://bugzilla.mozilla.org/show_bug.cgi?id=1950056 Mozilla Corporation Permissions Required 
https://bugzilla.mozilla.org/show_bug.cgi?id=1961777 Mozilla Corporation Permissions Required 
https://www.mozilla.org/security/advisories/mfsa2025-51/ Mozilla Corporation Vendor Advisory 
https://www.mozilla.org/security/advisories/mfsa2025-54/ Mozilla Corporation Vendor Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-434 Unrestricted Upload of File with Dangerous Type CISA-ADP  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

6 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-6435
NVD Published Date:
06/24/2025
NVD Last Modified:
04/13/2026
Source:
Mozilla Corporation