Re: Behavior analysis vs. Integrity analysis [was: Binary Bruteforcing]

From: Michal Zalewski (lcamtufat_private)
Date: Thu Mar 28 2002 - 12:30:16 PST

  • Next message: auto12012 auto12012: "Re: Behavior analysis vs. Integrity analysis [was: Binary Bruteforcing]"

    On Thu, 28 Mar 2002, auto12012 auto12012 wrote:
    
    > That is too bad. If you fail to understand that ftp daemon, in your
    > example, is not vulnerable because it adopts a behavior that it is not
    > excepted to follow, but simply because it compromises the integrity of
    > an object (root password)
    
    And how can you tell it does without examining the execution path? It is
    not enough to say that there is a situation where the compromise is
    possible because of insufficiently strict data flow control and
    separation, but you can't tell this is a threat unless you know it
    actually can happen.
    
    > If I do not believe vulnerability is related to execution path, it is
    > not because I believe it is not dependent of anything, but simply
    > because I believe it is dependent of something that is of much higher
    > abstraction: logic.
    
    We probably have a different understanding of the same term.
    "Vulnerability" as a term describing "broken behavioral logic" versus
    "vulnerability" describing actual problem that poses a real threat. The
    problem is that, first of all, building high-level abstracts in automated
    process does not always deliver complete models, and that with our
    existing code we have to deal with, in most cases, we'd be drowned in the
    sea of false positives triggered by detecting "approach that does not
    conform to established secure data flow models", but does not cause any
    actual exposure.
    
    -- 
    _____________________________________________________
    Michal Zalewski [lcamtufat_private] [security]
    [http://lcamtuf.coredump.cx] <=-=> bash$ :(){ :|:&};:
    =-=> Did you know that clones never use mirrors? <=-=
              http://lcamtuf.coredump.cx/photo/
    



    This archive was generated by hypermail 2b30 : Thu Mar 28 2002 - 13:46:29 PST