KDE 1.0's klock can be used to gain root priveledges

From: HD Moore (hdmooreat_private)
Date: Mon Nov 16 1998 - 17:57:51 PST

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    - --( the problem )--
    
    The SUID program klock shipped with KDE 1.0 attempts to execute
    kblankscrn.kss in the same directory as it.  If kblankscrn.kss cannot
    be executed (missing or mode -x) then klock will search the current
    user's $PATH for any executable with the same name and execute it as
    ROOT.  If no executable is found in the current path it gives this
    message:
    
        >Could not invoke kblankscrn.kss in $PATH or /opt/kde/bin
    
    Default modes for klock and kblankscrn.kss are:
    
    - -rwsr-xr-x   1 root     root         8760 Mar 12  1998 /opt/kde/bin/klock
    - -rwsr-xr-x   1 root     root        43600 Mar 12  1998
    /opt/kde/bin/kblankscrn.kss
    
    Systems Affected:   any system that runs KDE 1.0
    ____________________________________________________
    
    
    ( the exploit )
    
    This is only exploitable if any of the following occurs:
    
        1) klock is moved to another directory
        2) kblankscrn.kss is moved to another directory
        3) kblankscrn.kss is not executable
    
    To see if you are vulnerable...
    
    1) as root, chmod 600 /opt/kde/bin/kblankscrn.kss
    2) login as a normal user
    3) create a shell script thats looks like:
    
            #!/bin/sh
            echo Running script as `whoami`!
            exit
    
    4) name this script to kblankscrn.kss and mv to your home directory.
    5) execute /opt/kde/bin/klock, you should see:
    
        user@hostname:/home/user> /opt/kde/bin/klock
        user@hostname:/home/user> Running script as root!
    
    6) as root, chmod 755 /opt/kde/bin/kblankscrn.kss
    ____________________________________________________
    
    
    - --( the fix )--
    
    chmod 700 /opt/kde/bin/klock or wait until KDE is updated.
    the KDE buglist has been notified
    
    
    
    
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