{"id":821,"date":"2007-06-26T07:55:07","date_gmt":"2007-06-26T15:55:07","guid":{"rendered":"\/?p=821"},"modified":"2007-07-17T17:13:17","modified_gmt":"2007-07-18T01:13:17","slug":"control-not-nagging","status":"publish","type":"post","link":"https:\/\/www.identityblog.com\/?p=821","title":{"rendered":"Control, not nagging"},"content":{"rendered":"<p>In a piece called <a href=\"http:\/\/talk.bmc.com\/blogs\/blog-bohren\/jeff-bohren\/pleading-down-the-charges\" class=\"broken_link\">Pleading down the Charges<\/a>, Jeff Bohren of <a href=\"http:\/\/talk.bmc.com\/blogs\/blog-bohren\/jeff-bohren\" class=\"broken_link\">talkBMC&nbsp;<\/a>&nbsp;refers to the discussion I&#39;ve had with <a href=\"http:\/\/conorcahill.blogspot.com\/2007\/06\/saml-bashing.html\">Conor <\/a>about&nbsp;invisible redirection as &#8216;inflammatory&#8217;, and adds:&nbsp;<\/p>\n<p style=\"margin-left: 30px\">&#8220;In subsequent exchanges Kim and Conor plead the charges down from a felony to a misdemeanor. Kim&nbsp;allows that the redirection is OK so long as the IdP is completely trusted, but he is concerned about the case where the IdP is not trustworthy&#8230;<\/p>\n<p style=\"margin-left: 0px\">It&#39;s probably true that my &#8220;<a href=\"\/?p=815\">hand in wallet<\/a>&#8221; metaphor was a bit stark.&nbsp; But how can I put this?&nbsp; I&#39;m doing a threat analysis.&nbsp;&nbsp;Saying everything is OK because people are&nbsp;trustworthy really doesn&#39;t get us very far.&nbsp; Even a trustworthy IdP can be attacked;&nbsp; threats&nbsp;remain real even&nbsp;in the light of&nbsp;mitigations.&nbsp;<\/p>\n<p style=\"margin-left: 0px\">When we put on our <em>security hats<\/em>, and look at the security of a system, we try as hard as we can to explore every possible thing that can go wrong, and develop a complete profile of the attack vectors.&nbsp; No one says, &#8220;Hey,&nbsp;don&#39;t talk&nbsp;about that attack, because we&#39;ve done this or that to prevent it.&#8221;&nbsp; Instead, we list the attack, we list what we do to mitigate it, and we understand the vulnerability.&nbsp; We need to do the same thing around the privacy attack vectors.&nbsp; It is revealing that this doesn&#39;t seem to be our instinct at&nbsp;this point in time, and reminds me of the days, before the&nbsp;widespread vulnerability of computer systems became apparent,&nbsp;when people who brought up potential security vulnerabilities were sent to stand in the corner.<\/p>\n<p style=\"margin-left: 0px\">Jeff continues:<\/p>\n<p style=\"margin-left: 30px\">What is missing from this discussion is the point that &#8220;automatic redirection&#8221; is not mandated by SAML. Redirection, yes, but automatic redirection is not required. The SP could very well have presented at page to the user that says:<\/p>\n<p style=\"margin-left: 60px\" dir=\"ltr\"><em>&#8220;Your browser is about to be redirected <\/em><a href=\"http:\/\/www.youridp.com\/\" class=\"broken_link\"><font color=\"#006bb6\"><em>www.youridp.com<\/em><\/font><\/a><em> for the purposes of establishing your identity. If you consent to this redirection, press Continue. If you do not consent, press Cancel<\/em><strong>&#8230;.<\/strong><\/p>\n<p>Correct.&nbsp; This <em>could<\/em> be done.&nbsp; But information can also be made to fly around&nbsp;with zero visibility to the user.&nbsp; And that represents a risk.<\/p>\n<p>Jeff concludes:<\/p>\n<p style=\"margin-left: 30px\">Nobody does this kind of warning because the average user doesn\u00e2\u20ac\u2122t want to be bothered and isn\u00e2\u20ac\u2122t concerned with it. Not as concerned as, for instance, having a stranger reach into their pocket.<\/p>\n<p>Actually, thanks to &#8220;invisible system design&#8221;, the&nbsp;&#8220;average user&#8221; has no idea about how her personal information is being sent around, or that with redirection protocols, her own browser is the covert channel for&nbsp;sharing her&nbsp;identity information between sites.&nbsp;&nbsp;This might be all right inside an enterprise, when there is an implicit understanding that the enterprise shares all kinds of&nbsp;personal information.&nbsp; It might even be OK in a portal, where I go to a financial institution and expect it to share my information with its various departments and subsidiaries.&nbsp; But in the age of identity theft, I&#39;m not&nbsp;so sure she would not&nbsp;be concerned with the invisible exchange of identity information&nbsp;between contextually unrelated sites.&nbsp;&nbsp;I think&nbsp;she would probably&nbsp;feel&nbsp;like&nbsp;a stranger were reaching into her wallet.&nbsp;<\/p>\n<p>To be clear, my initial thinking about the &#8220;hand&nbsp;in wallet&#8221; came not from SAML, but from X.509, where the&nbsp;certificates described&nbsp;in&nbsp;<a href=\"\/?p=820\">Beyond maximal disclosure tokens<\/a>&nbsp;are routinely and automatically released to any site that asks for them without any user approval.&nbsp; SAML can be better in this regard, since the IP is able to judge the identity of the RP before releasing anything to it.&nbsp; In this sense, not just any hand can reach into your wallet &#8211; just&nbsp;a hand approved by the &#8220;card issuer&#8221;&#8230;&nbsp; This is better for sure.<\/p>\n<p>Do we need to nag users as Jeff suggests might be the alternative? No.&nbsp; Give the user a smart client, as is the case with CardSpace or Higgins, and whole new user experiences are possible that are &#8220;post nagging&#8221;.&nbsp; The invisibility threat is substantially reduced.<\/p>\n<p>In my next post in this series I&#39;m going to start looking at CardSpace and linkability.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>With SAML the IP can judge the identity of the RP before releasing anything to it.  So not just any hand that can reach into your wallet &#8211; just a hand approved by the card issuer&#8230;<\/p>\n","protected":false},"author":68,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[10,8,7,38,47,11,4],"tags":[],"_links":{"self":[{"href":"https:\/\/www.identityblog.com\/index.php?rest_route=\/wp\/v2\/posts\/821"}],"collection":[{"href":"https:\/\/www.identityblog.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.identityblog.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.identityblog.com\/index.php?rest_route=\/wp\/v2\/users\/68"}],"replies":[{"embeddable":true,"href":"https:\/\/www.identityblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=821"}],"version-history":[{"count":0,"href":"https:\/\/www.identityblog.com\/index.php?rest_route=\/wp\/v2\/posts\/821\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.identityblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=821"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.identityblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=821"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.identityblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=821"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}