CVE-2025-6435
published 2025-06-24CVE-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…
PriorityP345high8.1CVSS 3.1
AVNACHPRNUINSUCHIHAH
EPSS
0.37%
29.5th percentile
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.
Affected
5 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | firefox | < firefox 140.0-1 (sid) | firefox 140.0-1 (sid) |
| mozilla | firefox | < 140.0 | 140.0 |
| mozilla | firefox | — | — |
| mozilla | thunderbird | < 140.0 | 140.0 |
| mozilla | thunderbird | >= 0 < 1:140.7.1+build1-0ubuntu0.22.04.1 | 1:140.7.1+build1-0ubuntu0.22.04.1 |
CVSS provenance
nvdv3.18.1HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
osv8.1HIGH
vendor_debian8.1HIGH
vendor_redhat8.1HIGH
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Ubuntu
Thunderbird vulnerabilities
vendor_ubuntu·2026-02-02
CVE-2025-8031 Thunderbird vulnerabilities
Title: Thunderbird vulnerabilities
Summary: Several security issues were fixed in Thunderbird.
Multiple security issues were discovered in Thunderbird. If a user were
tricked into opening a specially crafted website in a browsing context,
an attacker could potentially exploit these to cause a denial of service,
obtain sensitive information, bypass security restrictions, cross-site
tracing, or execute arbitrary code.
Instructions: In general, a standard system update will make all the necessary changes.
Red Hat
firefox: Save as in Devtools could download files without sanitizing the extension
vendor_redhat·2025-06-24·CVSS 8.1
CVE-2025-6435 [HIGH] firefox: Save as in Devtools could download files without sanitizing the extension
firefox: Save as in Devtools could download files without sanitizing the extension
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 .download file extension. This could have led to the user inadvertently running a malicious executable.
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Package: firefox (Red Hat Enterprise Linux 10) - Not affected
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Not affected
Package: firefox (Red Hat Enterprise Linux 6) - Not affecte
Debian
CVE-2025-6435: firefox - If a user saved a response from the Network tab in Devtools using the Save As co...
vendor_debian·2025·CVSS 8.1
CVE-2025-6435 [HIGH] CVE-2025-6435: firefox - If a user saved a response from the Network tab in Devtools using the Save As co...
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.
Scope: local
sid: resolved (fixed in 140.0-1)
Mozilla
Mozilla Foundation Security Advisory 2025-54: CVE-2025-6435
vendor_mozilla·CVSS 8.1
CVE-2025-6435 [HIGH] Mozilla Foundation Security Advisory 2025-54: CVE-2025-6435
Mozilla Foundation Security Advisory 2025-54
CVE: CVE-2025-6435
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140
Mozilla
Mozilla Foundation Security Advisory 2025-51: CVE-2025-6435
vendor_mozilla·CVSS 8.1
CVE-2025-6435 [HIGH] Mozilla Foundation Security Advisory 2025-51: CVE-2025-6435
Mozilla Foundation Security Advisory 2025-51
CVE: CVE-2025-6435
Product: Firefox
Impact: high
Fixed in: Firefox 140
GHSA
GHSA-frfp-c23m-c888: 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 `
ghsa_unreviewed·2025-06-26
CVE-2025-6435 [HIGH] CWE-434 GHSA-frfp-c23m-c888: 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 `
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.
OSV
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 `
osv·2025-06-24·CVSS 8.1
CVE-2025-6435 [HIGH] 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 `
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.
No detection rules found.
No public exploits indexed.
2025-06-24
Published