CVE-2025-3522
Thunderbird External Attachment URL Processing Vulnerability
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.
INFO
Published Date :
April 15, 2025, 3:16 p.m.
Last Modified :
April 15, 2025, 7:16 p.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
3.4
Exploitability Score :
2.8
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-3522.
| URL | Resource |
|---|---|
| https://bugzilla.mozilla.org/show_bug.cgi?id=1955372 | |
| https://www.mozilla.org/security/advisories/mfsa2025-26/ | |
| https://www.mozilla.org/security/advisories/mfsa2025-27/ |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-3522 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-3522 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Apr. 15, 2025
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L Added CWE CWE-601 -
New CVE Received by [email protected]
Apr. 15, 2025
Action Type Old Value New Value Added 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. Added Reference https://bugzilla.mozilla.org/show_bug.cgi?id=1955372 Added Reference https://www.mozilla.org/security/advisories/mfsa2025-26/ Added Reference https://www.mozilla.org/security/advisories/mfsa2025-27/
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-3522 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-3522
weaknesses.