hacking logs

From: Jose Nazario (joseat_private)
Date: Thu Aug 09 2001 - 22:37:58 PDT

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    i wanted to ask if anyone know of any tools that explicitely are designed
    to basically hack logfiles but without getting access to the system (ie
    rm -f /var/log/SYSLOG). what you do is you abuse the server's respect of
    the backspace character to overwrite your malicious request with a more
    normal looking one.
    
    example:
    
    send in a request to a web server for, say ..\..\system32\cmd.exe but
    follow it up with ^H^H^H^H^HNormal Looking Log Entry ....
    
    simple nomad described this technique in a talk entitled "stealth
    communications across networks" at blackhat '00 and SANS '01. i've been
    coding a tool to implement some of his methods, this technique (the
    backspace one, or the huge buffer to overflow the flex scanner (1))
    included.
    
    any other tools out there to do this? mine may never see public release so
    ...
    
    notes:
    1. please see http://sec.subnet.dk/texts/ms-iis4-avoid-log.txt ... oh,
    this also works on netscape's server (or did as of IRIX 6.5).
    
    ____________________________
    jose nazario						     joseat_private
    	      	     PGP: 89 B0 81 DA 5B FD 7E 00  99 C3 B2 CD 48 A0 07 80
    				       PGP key ID 0xFD37F4E5 (pgp.mit.edu)
    
    
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