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.
CVSS
No CVSS.
References
| Link | Resource |
|---|---|
| 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 |
Configurations
Configuration 1 (hide)
|
History
18 Jun 2025, 13:26
| Type | Values Removed | Values Added |
|---|---|---|
| CPE | cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:* | |
| First Time |
Mozilla thunderbird
Mozilla |
|
| References | () https://www.mozilla.org/security/advisories/mfsa2025-26/ - Vendor Advisory | |
| References | () https://bugzilla.mozilla.org/show_bug.cgi?id=1955372 - Permissions Required | |
| References | () https://www.mozilla.org/security/advisories/mfsa2025-27/ - Vendor Advisory |
15 Apr 2025, 15:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2025-04-15 15:16
Updated : 2025-06-18 13:26
NVD link : CVE-2025-3522
Mitre link : CVE-2025-3522
JSON object : View
Products Affected
mozilla
- thunderbird
CWE
No CWE.