vulnerability
MFSA2025-45 Thunderbird: Security Vulnerabilities fixed in Thunderbird 139 (CVE-2025-5270)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 8 | (AV:N/AC:L/Au:N/C:C/I:N/A:N) | May 27, 2025 | May 28, 2025 | Apr 15, 2026 |
Severity
8
CVSS
(AV:N/AC:L/Au:N/C:C/I:N/A:N)
Published
May 27, 2025
Added
May 28, 2025
Modified
Apr 15, 2026
Description
In certain cases, SNI could have been sent unencrypted even when encrypted DNS was enabled. This vulnerability was fixed in Firefox 139 and Thunderbird 139.
Solution
mozilla-thunderbird-upgrade-139_0
Rapid7 Labs
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