Clarification on Xitami DoS

From: Matthew Murphy (mattmurphyat_private)
Date: Sun Aug 04 2002 - 15:24:24 PDT

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    Due to conflicting results in some tests, I believe that my
    previous post regarding this issue contained some inaccurate
    statements:
    
    The root cause of this vulnerability is not a sudden flood of
    connections; the issue appears to be that Xitami 2.5 Beta does
    not "clean up" the resources of a connection that has been
    broken/closed in some cases.  As a result, the vulnerability can
    be triggered simply by heavy traffic.
    
    Unsetting a limit you may have on HTTP connections will not
    avoid this vulnerability, and could worsen the affects of any
    actual overload.  However, systems with limits set will exceed 
    those limits more quickly.
    
    The vulnerability appears to be present in the way Xitami
    handles Keep-Alive connections.  Specifically, the server will
    not close Keep-Alive connections even when appropriate
    timeouts have been set.
    
    "The reason the mainstream is thought
    of as a stream is because it is
    so shallow."
                         - Author Unknown
    



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