CVEvulnerability
CVE-2025-3522
6.3 MEDIUM
Official page ↗
- Status
- Modified
- Published
- 2025-04-15
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)
- 6.3 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L
- Weaknesses
- CWE-601
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.
Affected configurations
• mozilla thunderbird (< 128.9.2)
• mozilla thunderbird (>= 129.0 < 137.0.2)
Related
Weakness · CWE (1)
- CWE-601 URL Redirection to Untrusted Site weakness
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1955372 Permissions Required
- https://www.mozilla.org/security/advisories/mfsa2025-26/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-27/ Vendor Advisory