[NT] Multiple Windows-Based FTP Servers Vulnerable to DoS under Windows 98

From: support@securiteam.com
Date: 08/02/01


From: support@securiteam.com
To: list@securiteam.com
Subject: [NT] Multiple Windows-Based FTP Servers Vulnerable to DoS under Windows 98
Message-Id: <20010802053711.381E313901@mail.der-keiler.de>
Date: Thu,  2 Aug 2001 07:37:11 +0200 (CEST)

The following security advisory is sent to the securiteam mailing list, and can be found at the SecuriTeam web site: http://www.securiteam.com

  Multiple Windows-Based FTP Servers Vulnerable to DoS under Windows 98
------------------------------------------------------------------------

SUMMARY

Several FTP server products running under Windows 98 (first edition) with
the 'CON\CON' kernel patch by Microsoft are vulnerable to a security
weakness that allows remote attackers to cause the program crash, bringing
down the whole operating system ("Blue screen of death").

DETAILS

Vulnerable systems:
BisonFTP version 4R1
Broker FTP Server version 5.9.5.0
G6 FTP Server version 2.15 (a.k.a. Bulletproof FTP Server)
GuildFTPD version 0.922
SurgeFTP version 2.0f
WarFTPD version 1.71
WFTPD version 3.00 R5

Immune systems:
ArGoSoft FTP Server version 1.2.2.2
Serv-U FTP Server version 3.0

Issuing a GET command with a DOS device name to the above vulnerable
servers, causes the products to strange behavior from consuming 100% CPU
time to completely crashing the computer.

Some FTP servers have filtering algorithms to prevent issuing a GET for
the 'AUX' device, but this filtering can easily be circumvented by
referring to the device as 'AUX.' (with a trailing dot).

ADDITIONAL INFORMATION

The information has been provided by <mailto:byterage@yahoo.com>
ByteRage.

========================================

This bulletin is sent to members of the SecuriTeam mailing list.
To unsubscribe from the list, send mail with an empty subject line and body to: list-unsubscribe@securiteam.com
In order to subscribe to the mailing list, simply forward this email to: list-subscribe@securiteam.com

====================
====================

DISCLAIMER:
The information in this bulletin is provided "AS IS" without warranty of any kind.
In no event shall we be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages.