Donato Ferrante


Application: Fastream NETFile FTP/Web Server
http://www.fastream.com/

Version: 6.5.1.980

Bug: Denial Of Service

Date: 19-Apr-2004

Author: Donato Ferrante
e-mail: fdonato@autistici.org
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:

"Secure, multi-threaded FTP/HTTP server combined, featuring automatic
virtual links, U/D ratios, quotas, authentication and extremely fast
directory and file caches. Other features include: User and group
permissions with permissions for all standard FTP and HTTP commands.
Serving from behind NAT/PAT. HTTP file uploading and management.
Free for personal use; professional license is required for commercial
usage."



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2. The bug:
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The program is unable to manage nonexistent usernames in the login
procedure. So attacker can deny the ftp service by sending crafted
USER and PASS strings.



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3. The code:
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To test the vulnerability:


1-a. connect to the ftp server and when it asks
for the USER, type: anUsername
for the PASS, type: aPassword


1-b. send to the ftp server something like:
USER anUsername
PASS aPassword



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4. The fix:
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Bug fixed in the version 6.5.1.981.



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