REWTERZ-20060503 - XM Easy Personal FTP Server Remote Buffer Overflow Vulnerability Release Date: May 3, 2006 Severity: High (Remote Code Execution) Vendor: Dxmsoft Software Affected: XM Easy Personal FTP Server v4.3 and before Operating Systems Affected: Windows NT 4.0 Windows 98 / ME Windows 2000 Windows XP Windows 2003 Overview: rewterz has discovered a critical vulnerability in XM Easy Personal FTP Server. This vulnerability may allow a remote attacker to overwrite memory with user controlled data and execute arbitrary code in the context of the user who executed the XM Easy Personal FTP Server. Technical Details: This vulnerability exists in the handling of username input provided by the user while making connection to FTP server. We chose not to provide detailed information about the vulnerability and how to reproduce it because the author hasn't confirmed this vulnerability. We can pass a long argument with some commands into a buffer. There is no checking of the length of this input. Depending on the input, this will cause exploitable condition. We have confirmed the ability to execute our own code. This is a common buffer overflow vulnerability and can be exploited easily. Credit: Discovery: Muhammad Ahmed Siddiqui Greetings: c0ntex Copyright (c) 2003-2006 rewterz Permission is hereby granted for the redistribution of this alert electronically. It is not to be edited in any way without express consent of rewterz. Disclaimer The information within this paper may change without notice. Use of this information constitutes acceptance for use in an AS IS condition. There are no warranties, implied or express, with regard to this information. In no event shall the author be liable for any direct or indirect damages whatsoever arising out of or in connection with the use or spread of this information. Any use of this information is at the user's own risk.