Textpattern XML-RPC TXP_RPCServer.php mt_uploadImage path traversal

A security vulnerability has been detected in Textpattern up to 4.9.1. Affected by this vulnerability is the function mt_uploadImage of the file rpc/TXP_RPCServer.php of the component XML-RPC Handler. The manipulation of the argument file.name leads to path traversal. Remote exploitation of the attack is possible. The exploit has been disclosed publicly and may be used. The vendor confirmed the issue and will provide a fix in the upcoming release.