CVE-2025-6435 describes a critical vulnerability in Firefox and Thunderbird versions prior to 140, where saving a network response from DevTools could omit the .download file extension, potentially leading users to execute malicious files inadvertently. With a CVSS score of 8.1 (HIGH), this vulnerability has a network attack vector and high impact on confidentiality, integrity, and availability, despite requiring high attack complexity. Currently, there is no evidence of active exploitation, public exploit code, or significant community discussion, and it is not listed on the KEV catalog.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 140.0CPE matchmatch criteria | cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:* | ||
< 140.0CPE matchmatch criteria | cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.2 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.