Re: 2.4.x/Slackware Init script vulnerability

From: twiz - Perla Enrico (twiat_private)
Date: Wed Jul 18 2001 - 16:50:07 PDT

  • Next message: Jeev: "RE: 2.4.x/Slackware Init script vulnerability"

    As Josh make me notice i' m partial in error.
    The problem was that i' ve installed kernel 2.4.5 on my box after
    (Slakware 7.0 come with kernel 2.2.13) , so I gave make modules_install at
    the end of the compilation : 
    
    if [ -r System.map ]; then /sbin/depmod -ae -F System.map  2.4.5; fi
    
    At the end depmod -a is called and it creates modules.dep, and it gives
    "-rw-r--r--" permissions.
    The Slakware startup script calls depmod -a, but modules.dep isn't erased
    before, but just "updated", so it keeps "-rw-r--r--" permissions.
    I' ve tried erasing modules.dep and then rebooting and modules.dep, this
    time beeing created, has , as Josh, said "-rw-rw-rw" permissions.
    
    So in the end this exploit will work only if the kernel hasn't benn
    recompiled with make modules_install (or depmod -a called otherwise
    not at the startup) of if modules.dep is erased before "depmod
    -a" at the startup (Slakware 7.0 init script doesn' t do that, so it is
    not vulnerable :) )
    
      I' m sorry for my partially erroneus post
    
        twiz - twizat_private or twiat_private - ./twlc
    



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