vulnerability
Ubuntu: USN-7991-1 (CVE-2025-6435): Thunderbird vulnerabilities
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 9 | (AV:N/AC:M/Au:N/C:C/I:C/A:C) | Jun 24, 2025 | Jun 26, 2025 | Apr 15, 2026 |
Severity
9
CVSS
(AV:N/AC:M/Au:N/C:C/I:C/A:C)
Published
Jun 24, 2025
Added
Jun 26, 2025
Modified
Apr 15, 2026
Description
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.
Solution
ubuntu-upgrade-thunderbird
References
- CVE-2025-6435
- https://attackerkb.com/topics/CVE-2025-6435
- CWE-434
- EUVD-EUVD-2025-19016
- UBUNTU-USN-7991-1
- https://bugzilla.mozilla.org/show_bug.cgi?id=1950056
- https://bugzilla.mozilla.org/show_bug.cgi?id=1961777
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2025-19016
- https://www.cve.org/CVERecord?id=CVE-2025-6435
- https://www.mozilla.org/en-US/security/advisories/mfsa2025-51/#CVE-2025-6435
- https://www.mozilla.org/security/advisories/mfsa2025-51/
Rapid7 Labs
2026 Global Threat Landscape Report
The predictive window has collapsed. Exploitation follows disclosure in days. See how attackers are accelerating and how to stay ahead.