OASIS ebXML Messaging Services TC

Re: Threat assessment,some dissent RE: [ebxml-msg] security problemwith ebXML MS

  • 1.  Re: Threat assessment,some dissent RE: [ebxml-msg] security problemwith ebXML MS

    Posted 11-13-2001 11:44
    >    The specification is ambiguous regarding the significance of MIME
    >    headers for payloads.
    
    That is a good point, but one that realistically can be fixed in the
    documentation.
    
    >    An adversary could construct a body part that would pass the digest
    >    calculation but the actual content would cause an implementation to
    >    take actions other than what was intended.
    
    Do I misunderstand, or isn't that equivalent to saying an adversary can
    find a hash collision?  If that's a concern, aren't *all* digital
    signatures at risk?
    Or do I misunderstand.
    
    > In security there are purists who insist on doing everything possible
    > and doing it right.  Even if one takes a more pragmatic view, the goal
    > needs to be that whatever you do you must do it right.  Adding digital
    > signatures that leave a clear and present vulnerability, however small,
    > is analogous to putting steel doors on a wooden house that still has
    > windows without bars.
    
    Physicians have the rule "first, do no harm."  I always figured
    security's analog is "first, document what is done." :)  If the windows
    are 20 feet up and the wooden is 8' redwood, that might be a valid
    security decision.
    
    If the spec is going to leave the ambiguity, then it probably should say
    why headers might need to be protected, and it should definitely say HOW
    to do so. I'm neutral on the "if", but think the the "then" should be
    done.
    
    The market will decide.  I betcha most businesses deploying ebXML over
    HTTP over VPN will not favor the vendor who spends the extra time and
    complexity. :)
    	/r$
    
    
    
    -- 
    Zolera Systems, Your Key to Online Integrity
    Securing Web services: XML, SOAP, Dig-sig, Encryption
    http://www.zolera.com