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Home >> Browse Vulnerability Assessment Database >> Denial of Service >> NT IIS Malformed HTTP Request Header DoS Vulnerability

Vulnerability Assessment Details

NT IIS Malformed HTTP Request Header DoS Vulnerability

Vulnerability Assessment Summary
Performs a denial of service against IIS

Detailed Explanation for this Vulnerability Assessment

It was possible to crash the remote web server
by sending a malformed header request, like :

GET / HTTP/1.1
Host: aaaaaaaaaaaa... (200 bytes)
Host: aaaaaaaaaaaa... (200 bytes)
... 10,000 lines ...
Host: aaaaaaaaaaaa... (200 bytes)

This flaw permits a possible hacker to shut down your
webserver, thus preventing legitimate users from
connecting to your web server.

Solution : See http://www.microsoft.com/technet/security/bulletin/ms99-029.mspx
if you are using IIS. Or else, contact the vendor of
your web server and notify it of this flaw.

Network Security Threat Level: High

Bugtraq Id : 579

Networks Security ID: 579

Vulnerability Assessment Copyright: This script is Copyright (C) 1999 Renaud Deraison

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