Re: Orange Web Server v2.1 DoS

[bert hubert <ahu () DS9A NL>]

On Tue, Feb 27, 2001 at 04:50:46AM -0000, slipy () B10Z NET wrote:

> invalid page fault. This is a very strange DoS, see
> example.

> echo "GET A" | telnet 192.168.0.20 80
>
> ^^ = That simple echo & pipe will cause this:
>
> ORANGEWEBSERVER caused an invalid page fault

This DoS is not so very strange, I've seen it a few times before. When
closing a TCP/IP connection very quickly after creating it, it is possible
for a server to try to send data to a closed connection repeatedly without
proper error checking (people don't expect a connection to die instantly
after it was created).

Under UNIX, you can catch or ignore SIGPIPE as a stopgap solution. Windows
will probably have something similar.

Regards,

bert

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