CVE-2025-6435

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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTNIST
8.1 HIGH
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
mozillaCNA
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CISA-ADPADP
8.1 HIGH
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Debian logo
Debian Releases
Debian Product
Codename
firefox
sid
140.0-1
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
firefox
plucky
not-affected
oracular
not-affected
noble
not-affected
jammy
not-affected
mozjs102
plucky
dne
oracular
dne
noble
ignored
jammy
ignored
mozjs115
plucky
ignored
oracular
ignored
noble
ignored
jammy
dne
mozjs38
plucky
dne
oracular
dne
noble
dne
jammy
dne
bionic
needs-triage
mozjs52
plucky
dne
oracular
dne
noble
dne
jammy
dne
focal
ignored
bionic
ignored
mozjs68
plucky
dne
oracular
dne
noble
dne
jammy
dne
focal
ignored
mozjs78
plucky
dne
oracular
dne
noble
dne
jammy
ignored
mozjs91
plucky
dne
oracular
dne
noble
dne
jammy
ignored
thunderbird
plucky
not-affected
oracular
not-affected
noble
not-affected
jammy
needed
Common Weakness Enumeration
Vulnerability Media Exposure
References
https://bugzilla.mozilla.org/show_bug.cgi?id=1950056
https://bugzilla.mozilla.org/show_bug.cgi?id=1961777
https://www.mozilla.org/security/advisories/mfsa2025-51/