vulnerability
MFSA2025-27 Thunderbird: Security Vulnerabilities fixed in Thunderbird ESR 128.9.2 (CVE-2025-3522)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:N/AC:M/Au:N/C:P/I:P/A:P) | Apr 15, 2025 | Apr 16, 2025 | Apr 15, 2026 |
Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Apr 15, 2025
Added
Apr 16, 2025
Modified
Apr 15, 2026
Description
Thunderbird processes the X-Mozilla-External-Attachment-URL header to handle attachments which can be hosted externally. When an email is opened, Thunderbird accesses the specified URL to determine file size, and navigates to it when the user clicks the attachment. Because the URL is not validated or sanitized, it can reference internal resources like chrome:// or SMB share file:// links, potentially leading to hashed Windows credential leakage and opening the door to more serious security issues. This vulnerability was fixed in Thunderbird 137.0.2 and Thunderbird 128.9.2.
Solution
mozilla-thunderbird-upgrade-128_9_2
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