Unicode Buffer Overflow in WinFtp Server 1.6.8
Donato Ferrante
Application: WinFtp Server
http://www.wftpserver.com
Version: 1.6.8
Bug: Unicode Buffer Overflow
Date: 17-Aug-2005
Author: Donato Ferrante
e-mail: fdonato@xxxxxxxxxxxxx
web: www.autistici.org/fdonato
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1. Description
2. The bug
3. The code
4. The fix
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1. Description:
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Vendor's Description:
"WinFTP Server is a multithreaded FTP server for Windows 98/NT/XP."
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2. The bug:
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The bug is located in the "Log To Screen" feature, this feature
allows the program to show server's log on screen.
By default the program has this function (called Log-SCR) enabled.
So a malicious user can trigger an unicode buffer overflow.
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3. The code:
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To test the vulnerability send a request to the FTP server like:
aaa [1024 of a] aaa
and then scroll down the log screen, so the server will crash.
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4. The fix:
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Vendor has been contacted.
Bug will be fixed in the next release.
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