Re: KDE Screensaver vulnerability

From: Henrik Nordstrom (hnoat_private)
Date: Wed Nov 18 1998 - 16:22:22 PST

  • Next message: Cy Schubert: "Re: 'sudo' recommendations"

    Jason Axley wrote:
    >
    > So, it sounds like now malicious users who can't read /etc/shadow in
    > order to grab encoded passwords to crack them can just do brute-force
    > password guessing without any lockout or auditing by simply piping
    > password guesses to the setuid kcheckpass program which will happily
    > check them against the shadow entries for correctness.
    
    If I understands it correctly they can only brute-force their own
    password... But if kcheckpass can be used to check any users password
    then I agree that this is a security risk.
    
    > Or maybe it would give up pieces of /etc/shadow from memory if
    > you could get it to coredump...
    
    Only if your run it on a system which allows coredumps for a suid/sgid
    program, which I think every one has agreed is a security risk in its
    own.
    
    And I also agree that kcheckpass should delay if the password is
    incorrect. This is to slow down any attempts to manually bruteforce a
    screen saver or any thing else relying on kcheckpass. It won't give any
    added security to the kcheckpass program, but to every program that uses
    it.
    
    ---
    Henrik Nordstrom
    



    This archive was generated by hypermail 2b30 : Fri Apr 13 2001 - 14:23:53 PDT