[REWTERZ-20060503] XM Easy Personal FTP Server Remote Buffer Overflow Vulnerability

[rewterz <advisories@xxxxxxxxxxx>]

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.

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