CVE-2025-6435 (GCVE-0-2025-6435)

Vulnerability from cvelistv5 – Published: 2025-06-24 12:28 – Updated: 2026-04-13 14:31
VLAI
Title
Save as in Devtools could download files without sanitizing the extension
Summary
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.
Severity
8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-06-24 13:37 UTC
CWE
  • CWE-434 - Unrestricted Upload of File with Dangerous Type
Assigner
References
Impacted products
Vendor Product Version
Mozilla Firefox Unaffected: 140 , ≤ * (rpm)
Create a notification for this product.
Mozilla Thunderbird Unaffected: 140 , ≤ * (rpm)
Create a notification for this product.
Credits
Ameen Basha M K
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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