NTMail Configuration Service DoS

Advisory Code:   VIGILANTE-2000008

Release Date:
September 4, 2000

Systems Affected:
- NTMail V5 Alpha Processor
- NTMail V5 Intel Processor
- NTMail V6 Alpha Processor
- NTMail V6 Intel Processor

THE PROBLEM
The web configuration running on TCP port 8000 does not flush incomplete
HTTP requests, and thus it is possible to use up all the server ressources
within a very short time. During testing the CPU usage stayed around 90-99%
and within 2 minutes the www.exe service had consumed more than 250MB of
memory. An attack might result in the service crashing, when the system hits
the maximum pagefile size.

Vendor Status:
Gordano was contacted on the 19th of August (Saturday) and a reply was
received on the 21st of August. On The 22nd of August we received a fix,
which appears to fix the problem.

Fix (quote from the vendor):
"Gordano Limited, developers of the award winning mail server NTMail, are
pleased to have worked with Vigilante.com to secure their product
and protect their customers from a potential DoS exploit."

NTMail V5 Alpha Processor fix URL:
ftp://ftp.gordano.com/ntmail5/hotfixes/ntmail5g_alpha_20000830.zip

NTMail V5 Intel Processor fix URL:
ftp://ftp.gordano.com/ntmail5/hotfixes/ntmail5g_intel_20000830.zip

NTMail V6 Alpha Processor fix URL:
ftp://ftp.gordano.com/ntmail6/hotfixes/ntmail6_alpha_20000830.zip

NTMail V6 Intel Processor fix URL:
ftp://ftp.gordano.com/ntmail6/hotfixes/ntmail6_intel_20000830.zip


Vendor   URL: http://www.gordano.com/
Product  URL: http://www.ntmail.co.uk/
Copyright VIGILANTe 2000-08-19

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