My home network uses a small 4 port broadband Dlink router (704p) The

firmware was updated a week ago.

The following malformed URL's cause odd behavior in the router. Pointing

your browser (like most routers) to the gateways internal IP address you

get a web interface for administering your router.

http://192.168.0.1/syslog.htm?

D=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAA

AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

This URL caused the router to do a DNS query on:

AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAA

AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA (at) xxxx.xx.comcast (dot) net [email concealed]

"@xxxx.xx.comcast.net" is the trailing end of my hostname (i replaced the

real trailing host name with x's as to not give up my location! heh)

Subsequently there was a DNS response "no such name"

Enough of these malformed URLS causes the DNS server to DoS the router for

a short time because a DNS response packet is much larger then a DNS query

packet.

This URL also caused an error in the routers log file page, the URL

made the page look odd. This router uses CSS to display its tabs and log

file (syslog.htm). Some of the HTML was visible within the CSS that were

now repeating across the page. I took a screen shot and uploaded it to my

webspace.

http://www.securityindex.net/router.JPG

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http://192.168.0.1/syslog.htm?

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This malformed URL caused the router to stop responding. Requesting this

url over and over will eventually render the router useless until reset.

You can still access the internet after sending this url once but the

routers configuration page does not respond until you reset the router.

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i sent an email to dlink containing a copy of this post. Thanx

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--chris

www.securityindex.net

-apex security group-

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