unusual http access in proxy log

["Martin K. Lee - XML Consulting" <martin.lee () xmlconsulting com au>]

All,
 
While I was checking a client's proxy log file, I found thousands of
http access from a few hosts to the follow URL:
http://www.instituto.com.br/attackDoS.php?ver=01&task=newzad&first=1
 
Has anyone seen this before?  I did a search in google and it seems like
it exists in quite a lot of proxy log.

Regards,
Martin K. Lee
Senior Consultant
martin.lee () xmlconsulting com au
PGP Fingerprint: DD34 4218 6D6E BB26 2D2C  F596 DE8A 58A8 C128 BCD1

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