vulnerability
Red Hat: CVE-2025-3522: thunderbird: Leak of hashed Window credentials via crafted attachment URL (Multiple Advisories)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:N/AC:M/Au:N/C:C/I:N/A:N) | Apr 15, 2025 | Apr 29, 2025 | Oct 13, 2025 |
Severity
7
CVSS
(AV:N/AC:M/Au:N/C:C/I:N/A:N)
Published
Apr 15, 2025
Added
Apr 29, 2025
Modified
Oct 13, 2025
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 affects Thunderbird < 137.0.2 and Thunderbird < 128.9.2.
Solutions
no-fix-redhat-rpm-packageredhat-upgrade-thunderbirdredhat-upgrade-thunderbird-debuginforedhat-upgrade-thunderbird-debugsource
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