When logging in to a Matrix account, Thunderbird used the homeserver address provided in the server's login response without validating it. A malicious or compromised homeserver could provide a file: URL, causing Thunderbird to send all further Matrix requests of that session to local files or, on Windows, to an attacker-controlled network share, which could leak the user's NTLM credentials.
The NTLM credential leak only affects Thunderbird on Windows. Other operating systems are unaffected. This vulnerability was fixed in Thunderbird 159 and Thunderbird 153.6.
The NTLM credential leak only affects Thunderbird on Windows. Other operating systems are unaffected. This vulnerability was fixed in Thunderbird 159 and Thunderbird 153.6.
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Tue, 27 Oct 2026 19:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Mozilla
Mozilla thunderbird |
|
| Vendors & Products |
Mozilla
Mozilla thunderbird |
Tue, 27 Oct 2026 18:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | When logging in to a Matrix account, Thunderbird used the homeserver address provided in the server's login response without validating it. A malicious or compromised homeserver could provide a file: URL, causing Thunderbird to send all further Matrix requests of that session to local files or, on Windows, to an attacker-controlled network share, which could leak the user's NTLM credentials. The NTLM credential leak only affects Thunderbird on Windows. Other operating systems are unaffected. This vulnerability was fixed in Thunderbird 159 and Thunderbird 153.6. | |
| Title | Matrix homeserver could redirect the chat session to a local file or network share | |
| References |
|
Projects
Sign in to view the affected projects.
Status: PUBLISHED
Assigner: mozilla
Published:
Updated: 2026-10-27T18:27:53.280Z
Reserved: 2026-10-27T18:16:33.089Z
Link: CVE-2026-118180
No data.
Status : Received
Published: 2026-10-27T19:17:29.693
Modified: 2026-10-27T19:17:29.693
Link: CVE-2026-118180
No data.
OpenCVE Enrichment
Updated: 2026-10-27T19:30:09Z
Weaknesses
No weakness.