Vulnerability · NVD

CVE-2025-6435

CVE-2025-6435, high severity (CVSS 8.1): 2 tracked apps concerned, all fixed or indeterminable on their current version.

Severity (CVSS): 8.1
Exploitation: 0.5 %
Tracked apps: 2
Still exposed: 0

Published on 2025-06-24

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.

Attack vector : Network No privileges required No user interaction

Show raw CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS 0.46% exploit very unlikely percentile 37.2%

Tracked apps referencing this CVE

For each app: the affected range, the fixing version, and where the tracked app stands today.

Mozilla Firefox Windows winget:Mozilla.Firefox

Affected <140.0 Fixed in 140.0 Latest tracked 157.0 patched

Observed affected builds (123)

139.0.4 139.0.1 139.0 138.0.4 138.0.3 138.0.1 138.0 137.0.2 137.0.1 137.0 136.0.4 136.0.3 136.0.2 136.0.1 136.0 135.0.1 135.0 134.0.2 134.0.1 134.0 133.0.3 133.0 132.0.2 132.0.1 132.0 131.0.3 131.0.2 131.0 130.0.1 130.0 +93 · see history
Mozilla Thunderbird Windows winget:Mozilla.Thunderbird

Affected <140.0 Fixed in 140.0 Latest tracked 157.0 patched

Observed affected builds (98)

139.0.2 139.0.1 139.0 138.0.2 138.0.1 138.0 137.0.2 137.0.1 137.0 136.0.1 136.0 115.14.0 115.13.0 115.12.2 115.12.1 115.11.1 115.11.0 115.10.2 115.10.1 115.10.0 115.9.0 115.8.1 115.8.0 115.7.0 115.6.1 115.6.0 115.5.2 115.5.1 115.4.2 115.4.1 +68 · see history

Vulnerable CPE configurations (2)

Vendor	Product	Platform	Versions	CPE 2.3 URI
mozilla	firefox All platforms (wildcard)	All platforms (wildcard)	<140.0	cpe:2.3:a:mozilla:firefox::::::::
mozilla	thunderbird All platforms (wildcard)	All platforms (wildcard)	<140.0	cpe:2.3:a:mozilla:thunderbird::::::::

View on NVD ↗ Advisory · www.mozilla.org

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