Matrix homeserver could redirect the chat session to a local file or network share
Impact
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.
Source excerpt · mozillaThe NTLM credential leak only affects Thunderbird on Windows.
Affected packages
Affected products
Vendor version evidence. Product records are separate from automatic dependency matching.
Mozilla · Thunderbird
| Version / range | Source status |
|---|---|
| 153.6 through 153.* (inclusive) | unaffected |
| 159 through * (inclusive) | unaffected |
Original source 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.