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<TITLE>Nonrepudiation, and Trusting OpenID Providers</TITLE>
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<FONT FACE="Calibri, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:11pt'>I have some concerns about OpenID, and I would like to see what those involved think about them.<BR>
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It seems to me that, regardless of how OpenID is deployed, it is always possible for an OpenID provider itself to authenticate with a relying party as any user by forging a request to authenticate using the user’s identifier. This is because a relying party cannot tell the difference between a user attempting to log in using his or her identifier, and the user’s OpenID provider spoofing that user to gain access to whatever services the relying party provides to that user. This seems to require that both users and relying parties put a lot of trust in OpenID providers: for example, if I used my OpenID identifier for online banking and email, my OpenID provider could easily access my email and bank account. <BR>
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Additionally, even if we assume that OpenID providers will not log into users’ accounts, I still cannot see how OpenID could provide nonrepudiation regarding messages sent to a relying party by an authenticated user: for example, if I authenticate with my bank using my OpenID identifier and then use the bank’s “bill pay” service to pay a bill, there’s no way the bank can prove that I ordered that payment because it is possible that someone working for my OpenID provider logged in as me and ordered it.<BR>
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Does anyone disagree with my analysis?<BR>
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Dylan</SPAN></FONT>
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