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    <title><![CDATA[[SecurityRatty] tag: cryptographic]]></title>
    <link>http://securityratty.com/tag/cryptographic</link>
    <description></description>
    <pubDate>Thu, 10 Jul 2008 20:00:00 +0000</pubDate>
    <generator>iRatty Engine</generator>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <item>
      <title><![CDATA[Will Passwords Become Obsolete?]]></title>
      <link>http://securityratty.com/article/f7dd714962f1e8f812f0f43645c379ba</link>
      <guid>http://securityratty.com/article/f7dd714962f1e8f812f0f43645c379ba</guid>
      <description><![CDATA[I cant keep track of how many different passwords I have, although I know its not nearly enough I tend to be lazy like most people and re-use the same passwords for many different accounts
But heres a...]]></description>
      <content:encoded><![CDATA[<p>I can&#8217;t keep track of how many different passwords I have, although I know it&#8217;s not nearly enough &#8212; I tend to be lazy like most people and re-use the same passwords for many different accounts.<br />
But here&#8217;s a new idea &#8212; what if passwords for online accounts were replaced entirely by cryptographic keys that sat on our desktops like icons, and functioned in the background, so we wouldn&#8217;t need to remember a string of letters or numbers?</p>
<p>An interesting <a rel="nofollow" target="_blank" href="http://www.novainfosecportal.com/2008/08/14/bye-bye-passwords-maybe/">blog post </a>this morning discusses the obstacles and implications of this kind of technology, in part quoting a recent New York Times article &#8212; </p>
<blockquote><p>
In short, we need a log-on system that relies on cryptography, not mnemonics. As users, we would replace passwords with so-called information cards, icons on our screen that we select with a click to log on to a Web site. The click starts a handshake between machines that relies on hard-to-crack cryptographic code.</p></blockquote>
<p>An obstacle to this kind of system are the current initiatives toward Open ID and single-sign on services, strategies that are backed by large industry players such as the Equifax, Google, Novell, Microsoft, Oracle, etc. In the open ID system, you would log in to a session on the web with one password, which would be accepted by any application/account supporting the open ID infrastructure. </p>
<p>To me Open ID sounds like a step backwards, toward less security&#8230;<br />
then again, I would think that encrypting everything could also make your system run significantly slower, and that it wouldn&#8217;t prevent all the risks either&#8230;</p>]]></content:encoded>
      <pubDate>Fri, 15 Aug 2008 09:46:48 +0000</pubDate>
      <category domain="http://securityratty.com/tag/passwords">passwords</category>
      <category domain="http://securityratty.com/tag/log-on system">log-on system</category>
      <category domain="http://securityratty.com/tag/log">log</category>
      <category domain="http://securityratty.com/tag/system">system</category>
      <category domain="http://securityratty.com/tag/replace passwords">replace passwords</category>
      <category domain="http://securityratty.com/tag/web site">web site</category>
      <category domain="http://securityratty.com/tag/click starts">click starts</category>
      <category domain="http://securityratty.com/tag/york times article">york times article</category>
      <category domain="http://securityratty.com/tag/online accounts">online accounts</category>
      <source url="http://feeds.feedburner.com/~r/itsecurity/~3/366003641/">Will Passwords Become Obsolete?</source>
    </item>
    <item>
      <title><![CDATA[Keyczar: Safe and Simple Cryptography]]></title>
      <link>http://securityratty.com/article/d7aad095f44d95efad0e3a3210dc4625</link>
      <guid>http://securityratty.com/article/d7aad095f44d95efad0e3a3210dc4625</guid>
      <description><![CDATA[Written by Steve Weis

Cryptography is notoriously hard to get right and if improperly used, can create serious security holes. Common mistakes include using the wrong cipher modes or obsolete...]]></description>
      <content:encoded><![CDATA[<span class="byline-author">Written by Steve Weis</span><br /><br /><img style="margin: 0pt 0pt 10px 10px; float: right;" src="http://2.bp.blogspot.com/_LMSk7hTEaIE/SKCABPuzeVI/AAAAAAAAhXc/nyKwkCyDdwQ/s200/keyczar_logo.jpg" alt="" id="BLOGGER_PHOTO_ID_5233323525895584082" border="0" />Cryptography is notoriously hard to get right and if improperly used, can create serious security holes. Common mistakes include using the wrong cipher modes or obsolete algorithms, composing primitives in an unsafe manner, hard-coding keys in source code, or failing to anticipate the need for future key rotation. With these risks in mind, we're pleased to announce the open-source release of <a href="http://www.keyczar.org/">Keyczar</a>.<br /><br />Keyczar is a cryptographic toolkit that supports encryption and authentication for both symmetric and public-key algorithms. It addresses some of the aforementioned issues by choosing safe defaults, tagging outputs with key version information, and providing a simple application programming interface. Keyczar's key versioning system makes it easy to rotate and revoke keys, without worrying about backward compatibility or making any changes to source code.<br /><br />We look forward to working with the open source community and continuing to make cryptography safer and easier to use. To download Keyczar or for more information, please visit our <a href="http://code.google.com/p/keyczar">Google Code project</a> and <a href="http://groups.google.com/group/keyczar-discuss">discussion group</a>.<div class="feedflare">
<a href="http://feeds.feedburner.com/~f/GoogleOnlineSecurityBlog?a=Xmjn2K"><img src="http://feeds.feedburner.com/~f/GoogleOnlineSecurityBlog?i=Xmjn2K" border="0"></img></a> <a href="http://feeds.feedburner.com/~f/GoogleOnlineSecurityBlog?a=G4qbKk"><img src="http://feeds.feedburner.com/~f/GoogleOnlineSecurityBlog?i=G4qbKk" border="0"></img></a>
</div><img src="http://feeds.feedburner.com/~r/GoogleOnlineSecurityBlog/~4/362162234" height="1" width="1"/>]]></content:encoded>
      <pubDate>Mon, 11 Aug 2008 07:06:00 +0000</pubDate>
      <category domain="http://securityratty.com/tag/keyczar">keyczar</category>
      <category domain="http://securityratty.com/tag/key">key</category>
      <category domain="http://securityratty.com/tag/future key rotation">future key rotation</category>
      <category domain="http://securityratty.com/tag/information">information</category>
      <category domain="http://securityratty.com/tag/key version information">key version information</category>
      <category domain="http://securityratty.com/tag/cryptography">cryptography</category>
      <category domain="http://securityratty.com/tag/download keyczar">download keyczar</category>
      <category domain="http://securityratty.com/tag/source code">source code</category>
      <category domain="http://securityratty.com/tag/cryptography safer">cryptography safer</category>
      <source url="http://feeds.feedburner.com/~r/GoogleOnlineSecurityBlog/~3/362162234/keyczar-safe-and-simple-cryptography.html">Keyczar: Safe and Simple Cryptography</source>
    </item>
    <item>
      <title><![CDATA[Hackers Vie to Win DefCon's Mystery Challenge]]></title>
      <link>http://securityratty.com/article/116ed2ace81eb2a3af8c187523b81d98</link>
      <guid>http://securityratty.com/article/116ed2ace81eb2a3af8c187523b81d98</guid>
      <description><![CDATA[One of DefCon's most difficult contests is the Mystery Challenge. Teams compete to solve a series of riddles and cryptographic conundrums in order to win a black badge that grants them DefCon...]]></description>
      <content:encoded><![CDATA[One of DefCon's most difficult contests is the Mystery Challenge.  Teams compete to solve a series of riddles and cryptographic conundrums in order to win a black badge that grants them DefCon admission for life.<br style="clear: both;"/>
  <img alt="" style="border: 0; height:1px; width:1px;" border="0" src="http://www.pheedo.com/img.phdo?i=7e5c28bc362f81acd16242d9ccc42b34" height="1" width="1"/>
<img src="http://www.pheedo.com/feeds/tracker.php?i=7e5c28bc362f81acd16242d9ccc42b34" style="display: none;" border="0" height="1" width="1" alt=""/><div class="feedflare">
<a href="http://feeds.feedburner.com/~f/wired/politics/privacy?a=W3JUHK"><img src="http://feeds.feedburner.com/~f/wired/politics/privacy?i=W3JUHK" border="0"></img></a> <a href="http://feeds.feedburner.com/~f/wired/politics/privacy?a=O2chpk"><img src="http://feeds.feedburner.com/~f/wired/politics/privacy?i=O2chpk" border="0"></img></a> <a href="http://feeds.feedburner.com/~f/wired/politics/privacy?a=eZsZfk"><img src="http://feeds.feedburner.com/~f/wired/politics/privacy?i=eZsZfk" border="0"></img></a> <a href="http://feeds.feedburner.com/~f/wired/politics/privacy?a=xXvIDK"><img src="http://feeds.feedburner.com/~f/wired/politics/privacy?i=xXvIDK" border="0"></img></a>
 <a href="http://feeds.wired.com/~f/wired/politics/security?a=hNGlcK"><img src="http://feeds.wired.com/~f/wired/politics/security?i=hNGlcK" border="0"></img></a> <a href="http://feeds.wired.com/~f/wired/politics/security?a=cywxik"><img src="http://feeds.wired.com/~f/wired/politics/security?i=cywxik" border="0"></img></a> <a href="http://feeds.wired.com/~f/wired/politics/security?a=ab8DCk"><img src="http://feeds.wired.com/~f/wired/politics/security?i=ab8DCk" border="0"></img></a> <a href="http://feeds.wired.com/~f/wired/politics/security?a=sFL7NK"><img src="http://feeds.wired.com/~f/wired/politics/security?i=sFL7NK" border="0"></img></a> </div><img src="http://feeds.feedburner.com/~r/wired/politics/privacy/~4/362153504" height="1" width="1"/><img src="http://feeds.wired.com/~r/wired/politics/security/~4/362153506" height="1" width="1"/>]]></content:encoded>
      <pubDate>Mon, 11 Aug 2008 05:17:00 +0000</pubDate>
      <category domain="http://securityratty.com/tag/defcon">defcon</category>
      <category domain="http://securityratty.com/tag/mystery challenge">mystery challenge</category>
      <category domain="http://securityratty.com/tag/defcon admission">defcon admission</category>
      <category domain="http://securityratty.com/tag/win">win</category>
      <category domain="http://securityratty.com/tag/black badge">black badge</category>
      <category domain="http://securityratty.com/tag/cryptographic conundrums">cryptographic conundrums</category>
      <category domain="http://securityratty.com/tag/difficult contests">difficult contests</category>
      <category domain="http://securityratty.com/tag/teams compete">teams compete</category>
      <category domain="http://securityratty.com/tag/solve">solve</category>
      <source url="http://feeds.wired.com/~r/wired/politics/security/~3/362153506/the-defcon-16-m.html">Hackers Vie to Win DefCon's Mystery Challenge</source>
    </item>
    <item>
      <title><![CDATA[The Virtues of Mature and Minimalist Cryptography]]></title>
      <link>http://securityratty.com/article/d82c34507632e6056a14f2b6d813410d</link>
      <guid>http://securityratty.com/article/d82c34507632e6056a14f2b6d813410d</guid>
      <description><![CDATA[This installment of Crypto Corner takes a concise look at some of the issues responsible for why cryptography usually ends up looking bad, in practice, and fails to establish the right threat model,...]]></description>
      <content:encoded><![CDATA[This installment of Crypto Corner takes a concise look at some of the issues responsible for why cryptography usually ends up looking bad, in practice, and fails to establish the right threat model, let alone realize it. Ultimately, this failure is largely due to a lack of cryptographic competence and the dreaded habit of crammed-in-and-cobbled-together design.<br style="clear: both;"/>
  <img alt="" style="border: 0; height:1px; width:1px;" border="0" src="http://www.pheedo.com/img.phdo?i=8c95f87d6b9ff64547e75d1e75ec9a60" height="1" width="1"/>
<img src="http://www.pheedo.com/feeds/tracker.php?i=8c95f87d6b9ff64547e75d1e75ec9a60" style="display: none;" border="0" height="1" width="1" alt=""/>]]></content:encoded>
      <pubDate>Thu, 31 Jul 2008 09:30:24 +0000</pubDate>
      <category domain="http://securityratty.com/tag/crypto corner takes">crypto corner takes</category>
      <category domain="http://securityratty.com/tag/issues responsible">issues responsible</category>
      <category domain="http://securityratty.com/tag/threat model">threat model</category>
      <category domain="http://securityratty.com/tag/cryptography">cryptography</category>
      <category domain="http://securityratty.com/tag/cryptographic competence">cryptographic competence</category>
      <category domain="http://securityratty.com/tag/ultimately">ultimately</category>
      <category domain="http://securityratty.com/tag/due">due</category>
      <category domain="http://securityratty.com/tag/concise">concise</category>
      <category domain="http://securityratty.com/tag/design">design</category>
      <source url="http://www.pheedo.com/click.phdo?i=8c95f87d6b9ff64547e75d1e75ec9a60">The Virtues of Mature and Minimalist Cryptography</source>
    </item>
    <item>
      <title><![CDATA[A sneak peek at a Black Hat presentation]]></title>
      <link>http://securityratty.com/article/181fe8daaf5608a4eaded35d8d32675f</link>
      <guid>http://securityratty.com/article/181fe8daaf5608a4eaded35d8d32675f</guid>
      <description><![CDATA[No, it is not the Dan K DNS presentation, sorry. Patrick McGregor, CEO of BitArmor Systems is presenting at Black Hat as well. As part of our promotion with the SBN and Black Hat I have made my blog...]]></description>
      <content:encoded><![CDATA[<p>No, it is not the Dan K DNS presentation, sorry.  Patrick McGregor, CEO of BitArmor Systems is presenting at Black Hat as well.  As part of our promotion with the SBN and Black Hat I have made my blog available to Patrick to give us a sneak peek at his presentation.  Patrick was nice enough to prepare the following:</p>  <h4>Braving the Cold (Boot) – A Sneak Peek of My Presentation at Black Hat</h4>  <p>by Patrick McGregor</p>  <p>Cold boot attacks aren’t theoretical academic exercises. Cold boot attacks are real. And they’re serious.</p>  <p>In the past few years, companies have poured hundreds of millions of dollars into full disk encryption technologies. Companies expect full disk encryption to reduce the risk of exposure of sensitive information such as intellectual property or customer data. Reality often deviates from what is expected, however. Researchers from Princeton shocked the industry earlier in 2008 when they released a <a href="http://citp.princeton.edu/memory/">research paper</a> that showed that low-cost “Cold Boot” attacks could be used to defeat the security of most full disk encryption systems. They <a href="http://bitarmor.blogspot.com/2008/07/for-your-hacking-pleasure-cold-boot.html">recently even published</a> all the tools needed to do this at home!</p>  <p>Some have argued that Cold Boot attacks are not serious security threats. I disagree! First, an unskilled person can capitalize on the exploit using <a href="http://securosis.com/2008/03/27/uh-oh-time-to-take-cold-boot-encryption-attacks-very-seriously/">simple, automated steps</a> and <a href="http://mcgrewsecurity.com/projects/msramdmp/">publicly available tools</a>. In fact, Cold Boot attacks require nothing more than plugging a USB drive into a laptop. Second, the physical target of a Cold Boot attack, such as a laptop, is very easily obtainable (see the <a href="http://www.networkworld.com/news/2008/063008-laptops-lost-like-hot-cakes.html">recent Ponemon report</a> on laptops lost/stolen in airports – scary!). Third, although many laptops and desktops are stolen via random acts of theft, it is well known that some criminals profit from organized, calculated data theft. It is only a matter of time before we hear of a high-profile data breach that results from a simple Cold Boot attack.</p>  <p>I am excited to <a href="http://www.blackhat.com/html/bh-usa-08/bh-usa-08-speakers.html#McGregor">present at Black Hat</a> several innovations for preventing Cold Boot attacks. In addition to summarizing how a Cold Boot attack works, I’ll describe four new software techniques for hardening full disk encryption against the attacks. The software technology was developed by myself, Tim Hollebeek, Alexander Volynkin, and Matt White. All of us work for <a href="http://www.bitarmor.com/">BitArmor,</a> an exciting security startup based in Pittsburgh. Here’s a sneak peek:</p>  <p>· <b>Wash up</b>: Wipe keys immediately before certain OS state transitions, such as before the computer shuts down or goes into hibernation mode – accessing the memory will yield nothing. </p>  <p>· <b>Take advantage of BIOS memory smashing</b>: By strategically placing keys in certain regions of memory, we can rely on the BIOS boot process to overwrite keys before any operating system can dump the contents of memory.</p>  <p>· <b>Is it chilly in here?</b>: Using built-in temperature sensors, we can lock down the system in reaction to temperature drops that may indicate a Cold Boot attack is in progress.</p>  <p>· <b>Create a virtual enclave for keys</b>: We can implement special cryptographic, OS and processor architecture techniques to provide robust protection for keys against the most aggressive cold boot attacks. By creating a “virtual secure enclave” for encryption keys in software, an attacker cannot extract critical keys from memory – even if the RAM is super-cooled.</p>  <p>Hope you can join us at Black Hat as we take an <a href="http://www.blackhat.com/html/bh-usa-08/bh-usa-08-speakers.html#McGregor">in-depth look</a> at the future of full disk encryption technology.</p>
<p><a href="http://feeds.feedburner.com/~a/StillsecureAfterAllTheseYears?a=GGsLbi"><img src="http://feeds.feedburner.com/~a/StillsecureAfterAllTheseYears?i=GGsLbi" border="0"></img></a></p><div class="feedflare">
<a href="http://feeds.feedburner.com/~f/StillsecureAfterAllTheseYears?a=tvgRLJ"><img src="http://feeds.feedburner.com/~f/StillsecureAfterAllTheseYears?i=tvgRLJ" border="0"></img></a> <a href="http://feeds.feedburner.com/~f/StillsecureAfterAllTheseYears?a=TafXWJ"><img src="http://feeds.feedburner.com/~f/StillsecureAfterAllTheseYears?i=TafXWJ" border="0"></img></a> <a href="http://feeds.feedburner.com/~f/StillsecureAfterAllTheseYears?a=IRPnWJ"><img src="http://feeds.feedburner.com/~f/StillsecureAfterAllTheseYears?i=IRPnWJ" border="0"></img></a> <a href="http://feeds.feedburner.com/~f/StillsecureAfterAllTheseYears?a=xFRbVJ"><img src="http://feeds.feedburner.com/~f/StillsecureAfterAllTheseYears?i=xFRbVJ" border="0"></img></a> <a href="http://feeds.feedburner.com/~f/StillsecureAfterAllTheseYears?a=cwAU8j"><img src="http://feeds.feedburner.com/~f/StillsecureAfterAllTheseYears?i=cwAU8j" border="0"></img></a> <a href="http://feeds.feedburner.com/~f/StillsecureAfterAllTheseYears?a=7pGUFj"><img src="http://feeds.feedburner.com/~f/StillsecureAfterAllTheseYears?i=7pGUFj" border="0"></img></a>
</div><img src="http://feeds.feedburner.com/~r/StillsecureAfterAllTheseYears/~4/350948771" height="1" width="1"/>]]></content:encoded>
      <pubDate>Wed, 30 Jul 2008 14:08:27 +0000</pubDate>
      <category domain="http://securityratty.com/tag/boot">boot</category>
      <category domain="http://securityratty.com/tag/bios boot process">bios boot process</category>
      <category domain="http://securityratty.com/tag/cold boot attacks">cold boot attacks</category>
      <category domain="http://securityratty.com/tag/attacks">attacks</category>
      <category domain="http://securityratty.com/tag/cold">cold</category>
      <category domain="http://securityratty.com/tag/black hat">black hat</category>
      <category domain="http://securityratty.com/tag/disk encryption">disk encryption</category>
      <category domain="http://securityratty.com/tag/keys">keys</category>
      <category domain="http://securityratty.com/tag/wipe keys immediately">wipe keys immediately</category>
      <source url="http://feeds.feedburner.com/~r/StillsecureAfterAllTheseYears/~3/350948771/a-sneak-peek-at.html">A sneak peek at a Black Hat presentation</source>
    </item>
    <item>
      <title><![CDATA[The DNS Vulnerability]]></title>
      <link>http://securityratty.com/article/2fa89601e50143e1b069f4876ad01123</link>
      <guid>http://securityratty.com/article/2fa89601e50143e1b069f4876ad01123</guid>
      <description><![CDATA[Despite the best efforts of the security community, the details of a critical internet vulnerability discovered by Dan Kaminsky about six months ago have leaked. Hackers are racing to produce exploit...]]></description>
      <content:encoded><![CDATA[<p>Despite the best efforts of the security community, the details of a critical internet vulnerability discovered by Dan Kaminsky about six months ago have leaked. Hackers are racing to produce exploit code, and network operators who haven't already patched the hole are scrambling to catch up. The whole mess is a good illustration of the problems with researching and disclosing flaws like this.</p>

<p>The <a href="http://darkoz.com/?p=15">details</a> of the <a href="http://blog.invisibledenizen.org/2008/07/kaminskys-dns-issue-accidentally-leaked.html">vulnerability</a> aren't important, but basically it's a form of DNS cache poisoning. The DNS system is what translates domain names people understand, like www.schneier.com, to IP addresses computers understand: 204.11.246.1. There is a whole family of vulnerabilities where the DNS system on your computer is fooled into thinking that the IP address for www.badsite.com is really the IP address for www.goodsite.com -- there's no way for you to tell the difference -- and that allows the criminals at www.badsite.com to trick you into doing all sorts of things, like giving up your bank account details. Kaminsky discovered a particularly nasty variant of this cache-poisoning attack.</p>

<p>Here's the way the timeline was supposed to work: Kaminsky discovered the vulnerability about six months ago, and quietly worked with vendors to patch it. (There's a fairly straightforward fix, although the implementation nuances are complicated.) Of course, this meant describing the vulnerability to them; why would companies like Microsoft and Cisco believe him otherwise? On July 8, he held a <a href="http://news.bbc.co.uk/2/hi/technology/7496735.stm">press conference</a> to <a href="http://www.doxpara.com/?p=1162">announce</a> the <a href="http://www.kb.cert.org/vuls/id/800113">vulnerability</a> -- but not the details -- and reveal that a patch was available from a long list of vendors. We would all have a month to patch, and Kaminsky would release details of the vulnerability at the <a href="http://www.blackhat.com/html/bh-usa-08/bh-us-08-main.html">BlackHat</a> conference early next month.</p>

<p>Of course, the details <a href="http://it.slashdot.org/it/08/07/21/2212227.shtml">leaked</a>. <a href="http://blog.wired.com/27bstroke6/2008/07/details-of-dns.html">How</a> isn't important; it could have leaked a zillion different ways. Too many people knew about it for it to remain secret. Others who knew the general idea were too smart <a href="http://addxorrol.blogspot.com/2008/07/on-dans-request-for-no-speculation.html">not to speculate</a> on the details. I'm kind of amazed the details remained secret for this long; undoubtedly it had leaked into the underground community before the public leak two days ago. So now everyone who back-burnered the problem is rushing to patch, while the hacker community is racing to produce working exploits. </p>

<p>What's the moral here? It's easy to condemn Kaminsky: If he had shut up about the problem, we wouldn't be in this mess. But that's just wrong. Kaminsky found the vulnerability by accident. There's no reason to believe he was the first one to find it, and it's ridiculous to believe he would be the last. Don't shoot the messenger. The problem is with the DNS protocol; it's insecure.</p>

<p>The real lesson is that the <a href="http://www.schneier.com/crypto-gram-0103.html#1">patch treadmill</a> doesn't work, and it hasn't for years. This cycle of finding security holes and rushing to patch them before the bad guys exploit those vulnerabilities is expensive, inefficient and incomplete. We need to design security into our systems right from the beginning. We need <a href="http://www.schneier.com/blog/archives/2007/08/assurance.html">assurance</a>. We need security engineers involved in system design. This process won't prevent every vulnerability, but it's much more secure -- and cheaper -- than the patch treadmill we're all on now.</p>

<p>What a security engineer brings to the problem is a particular <a href="http://www.schneier.com/blog/archives/2008/03/the_security_mi.html">mindset</a>. He thinks about systems from a security perspective. It's not that he discovers all possible attacks before the bad guys do; it's more that he anticipates potential types of attacks, and defends against them even if he doesn't know their details. I see this all the time in good cryptographic designs. It's over-engineering based on intuition, but if the security engineer has good intuition, it generally works.</p>

<p>Kaminsky's vulnerability is a perfect example of this. Years ago, cryptographer Daniel J. Bernstein <a href="http://cr.yp.to/djbdns/forgery.html">looked at DNS security</a> and decided that Source Port Randomization was a smart design choice. That's exactly the work-around being rolled out now following Kaminsky's discovery. Bernstein didn't discover Kaminsky's attack; instead, he saw a general class of attacks and realized that this enhancement could protect against them. Consequently, the DNS program he wrote in 2000, <a href="http://cr.yp.to/djbdns/dnscache.html">djbdns</a>, doesn't need to be patched; it's already immune to Kaminsky's attack.</p>

<p>That's what a good design looks like. It's not just secure against known attacks; it's also secure against unknown attacks. We need more of this, not just on the internet but in voting machines, ID cards, transportation payment cards ... everywhere. Stop assuming that systems are secure unless demonstrated insecure; start assuming that systems are insecure unless designed securely.</p>

<p>This essay <a href="http://www.wired.com/politics/security/commentary/securitymatters/2008/07/securitymatters_0723">previously appeared</a> on Wired.com.</p><div class="feedflare">
<a href="http://feeds.feedburner.com/~f/schneier/fulltext?a=mOWtcJ"><img src="http://feeds.feedburner.com/~f/schneier/fulltext?i=mOWtcJ" border="0"></img></a> <a href="http://feeds.feedburner.com/~f/schneier/fulltext?a=xoZIeJ"><img src="http://feeds.feedburner.com/~f/schneier/fulltext?i=xoZIeJ" border="0"></img></a>
</div>]]></content:encoded>
      <pubDate>Tue, 29 Jul 2008 02:01:52 +0000</pubDate>
      <category domain="http://securityratty.com/tag/vulnerability">vulnerability</category>
      <category domain="http://securityratty.com/tag/kaminsky">kaminsky</category>
      <category domain="http://securityratty.com/tag/dan kaminsky">dan kaminsky</category>
      <category domain="http://securityratty.com/tag/details">details</category>
      <category domain="http://securityratty.com/tag/critical internet vulnerability">critical internet vulnerability</category>
      <category domain="http://securityratty.com/tag/bank account details">bank account details</category>
      <category domain="http://securityratty.com/tag/discover kaminsky">discover kaminsky</category>
      <category domain="http://securityratty.com/tag/patch">patch</category>
      <category domain="http://securityratty.com/tag/release details">release details</category>
      <source url="http://www.schneier.com/blog/archives/2008/07/the_dns_vulnera.html">The DNS Vulnerability</source>
    </item>
    <item>
      <title><![CDATA[Security Matters: Lesson From the DNS Bug: Patching Isn't Enough]]></title>
      <link>http://securityratty.com/article/91e8b8fee8fdb20a8381e76c3ea40942</link>
      <guid>http://securityratty.com/article/91e8b8fee8fdb20a8381e76c3ea40942</guid>
      <description><![CDATA[Despite the best efforts of the security community, the details of a critical internet vulnerability discovered by Dan Kaminsky about six months ago have leaked. Hackers are racing to produce exploit...]]></description>
      <content:encoded><![CDATA[<p>
Despite the best efforts of the security community, the details of a critical internet vulnerability discovered by Dan Kaminsky about six months ago have leaked. Hackers are racing to produce exploit code, and network operators who haven't already patched the hole are scrambling to catch up. The whole mess is a good illustration of the problems with researching and disclosing flaws like this.
</p><p>
The <a href="http://darkoz.com/?p=15">details</a> of the <a href="http://blog.invisibledenizen.org/2008/07/kaminskys-dns-issue-accidentally-leaked.html">vulnerability</a> aren't important, but basically it's a form of DNS cache poisoning. The DNS system is what translates domain names people understand, like www.schneier.com, to IP addresses computers understand: 204.11.246.1. There is a whole family of vulnerabilities where the DNS system on your computer is fooled into thinking that the IP address for www.badsite.com is really the IP address for www.goodsite.com -- there's no way for you to tell the difference -- and that allows the criminals at www.badsite.com to trick you into doing all sorts of things, like giving up your bank account details. Kaminsky discovered a particularly nasty variant of this cache-poisoning attack.
</p><p>
Here's the way the timeline was supposed to work: Kaminsky discovered the vulnerability about six months ago, and quietly worked with vendors to patch it. (There's a fairly straightforward fix, although the implementation nuances are complicated.) Of course, this meant describing the vulnerability to them; why would companies like Microsoft and Cisco believe him otherwise? On July 8, he held a <a href="http://news.bbc.co.uk/2/hi/technology/7496735.stm">press conference</a> to <a href="http://www.doxpara.com/?p=1162">announce</a> the <a href="http://www.kb.cert.org/vuls/id/800113">vulnerability</a> -- but not the details -- and reveal that a patch was available from a long list of vendors. We would all have a month to patch, and Kaminsky would release details of the vulnerability at the <a href="http://www.blackhat.com/html/bh-usa-08/bh-us-08-main.html">BlackHat</a> conference early next month.
</p><p>
Of course, the details <a href="http://it.slashdot.org/it/08/07/21/2212227.shtml">leaked</a>. <a href="http://blog.wired.com/27bstroke6/2008/07/details-of-dns.html">How</a> isn't important; it could have leaked a zillion different ways. Too many people knew about it for it to remain secret. Others who knew the general idea were too smart <a href="http://addxorrol.blogspot.com/2008/07/on-dans-request-for-no-speculation.html">not to speculate</a> on the details. I'm kind of amazed the details remained secret for this long; undoubtedly it had leaked into the underground community before the public leak two days ago. So now everyone who back-burnered the problem is rushing to patch, while the hacker community is racing to produce working exploits. 
</p><p>
What's the moral here? It's easy to condemn Kaminsky: If he had shut up about the problem, we wouldn't be in this mess. But that's just wrong. Kaminsky found the vulnerability by accident. There's no reason to believe he was the first one to find it, and it's ridiculous to believe he would be the last. Don't shoot the messenger. The problem is with the DNS protocol; it's insecure.
</p><p>
The real lesson is that the <a href="http://www.schneier.com/crypto-gram-0103.html#1">patch treadmill</a> doesn't work, and it hasn't for years. This cycle of finding security holes and rushing to patch them before the bad guys exploit those vulnerabilities is expensive, inefficient and incomplete. We need to design security into our systems right from the beginning. We need <a href="http://www.schneier.com/blog/archives/2007/08/assurance.html">assurance</a>. We need security engineers involved in system design. This process won't prevent every vulnerability, but it's much more secure -- and cheaper -- than the patch treadmill we're all on now.
</p><p>
What a security engineer brings to the problem is a particular <a href="http://www.schneier.com/blog/archives/2008/03/the_security_mi.html">mindset</a>. He thinks about systems from a security perspective. It's not that he discovers all possible attacks before the bad guys do; it's more that he anticipates potential types of attacks, and defends against them even if he doesn't know their details. I see this all the time in good cryptographic designs. It's over-engineering based on intuition, but if the security engineer has good intuition, it generally works.
</p><p>
Kaminsky's vulnerability is a perfect example of this. Years ago, cryptographer Daniel J. <a href="http://cr.yp.to/djbdns/forgery.html">Bernstein looked at DNS security</a> and decided that Source Port Randomization was a smart design choice. That's exactly the work-around being rolled out now following Kaminsky's discovery. Bernstein didn't discover Kaminsky's attack; instead, he saw a general class of attacks and realized that this enhancement could protect against them. Consequently, the DNS program he wrote in 2000, <a href="http://cr.yp.to/djbdns/dnscache.html">djbdns</a>, doesn't need to be patched; it's already immune to Kaminsky's attack.
</p><p>
That's what a good design looks like. It's not just secure against known attacks; it's also secure against unknown attacks. We need more of this, not just on the internet but in voting machines, ID cards, transportation payment cards ... everywhere. Stop assuming that systems are secure unless demonstrated insecure; start assuming that systems are insecure unless designed securely.
</p>
<p>
---
</p>
<p><em>Bruce Schneier is chief security technology officer of BT, and author of </em>Beyond Fear: Thinking Sensibly About Security in an Uncertain World<em>.</em>
</p><br style="clear: both;"/>
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      <pubDate>Wed, 23 Jul 2008 15:00:00 +0000</pubDate>
      <category domain="http://securityratty.com/tag/security">security</category>
      <category domain="http://securityratty.com/tag/security engineer">security engineer</category>
      <category domain="http://securityratty.com/tag/security engineer brings">security engineer brings</category>
      <category domain="http://securityratty.com/tag/security holes">security holes</category>
      <category domain="http://securityratty.com/tag/smart design choice">smart design choice</category>
      <category domain="http://securityratty.com/tag/design">design</category>
      <category domain="http://securityratty.com/tag/security engineers">security engineers</category>
      <category domain="http://securityratty.com/tag/kaminsky">kaminsky</category>
      <category domain="http://securityratty.com/tag/dan kaminsky">dan kaminsky</category>
      <source url="http://feeds.wired.com/~r/wired/politics/security/~3/344028448/securitymatters_0723">Security Matters: Lesson From the DNS Bug: Patching Isn't Enough</source>
    </item>
    <item>
      <title><![CDATA[Assessing the Security Benefits of Cloud Computing]]></title>
      <link>http://securityratty.com/article/1e09e5c89f15d3a4df4ea921f9230c2d</link>
      <guid>http://securityratty.com/article/1e09e5c89f15d3a4df4ea921f9230c2d</guid>
      <description><![CDATA[With all this talk and reporting about security concerns, lets change the channel for a moment and assess the potential security benefits of Cloud Computing
In my view, there are some strong technical...]]></description>
      <content:encoded><![CDATA[<p><a title="Is the glass half empty or half full?" href="http://www.flickr.com/photos/94094843@N00/2292559560/" target="_blank"><img class="alignright" style="border: 0; float: right; margin: 3px;" src="http://farm4.static.flickr.com/3004/2292559560_378f226531_m.jpg" border="0" alt="Is the glass half empty or half full?" /></a></p>
<p>With all this <a href="http://cloudsecurity.org">talk</a> and <a href="http://www.gartner.com/DisplayDocument?id=685308">reporting</a> about security concerns, lets change the channel for a moment and assess the <strong>potential security benefits</strong> of Cloud Computing.</p>
<p>In my view, there are some strong technical security arguments in favour of Cloud Computing - assuming we can find ways to manage the risks.</p>
<p>With this new paradigm come challenges <strong>and </strong>opportunities.  The challenges are getting plenty of attention - I&#8217;m regularly afforded the opportunity to <a href="http://www.gridtoday.com/grid/2422309.html">comment</a> on them, plus obviously I cover them on this blog.  However, lets not lose sight of the potential upside.</p>
<p>In this post, I walk through seven technical security benefits.  Some are immediate, others may arise over time and have conditions attached (some unstated for the sake of brevity).  However, I&#8217;m including the longer-range benefits now to raise awareness.  Some of the outcomes listed are available today without the Cloud, but they are either complex and slow to implement (and thus less likely to happen) or prohibitive for capital cost reasons.  I don&#8217;t claim this is a definitive list - it reflects where my thinking is today.</p>
<p>Some benefits depend on the Cloud service used and therefore do not apply across the board.  For example; I see no solid forensic benefits with SaaS.  Also, for space reasons, I&#8217;m purposely not including the &#8216;flip side&#8217; to these benefits, however if you read this blog regularly you should <a href="http://cloudsecurity.org/2008/04/24/cloud-stacks-please-mind-the-gap/">recognise some</a>.</p>
<p>On a sidenote, I believe the Cloud offers Small and Medium Businesses major potential security benefits.  Frequently SMBs struggle with limited or non-existent in-house INFOSEC resources and budgets.  The caveat is that the Cloud market is still very new - security offerings are somewhat foggy - making selection tricky.  Clearly, not all Cloud providers will offer the same security.</p>
<h4>Seven Technical Security Benefits of the Cloud</h4>
<h4>1. Centralised Data</h4>
<ul>
<li><strong>Reduced Data Leakage</strong>: this is the benefit I hear most from Cloud providers - and in my view they are right.  How many laptops do we need to lose before we get this?  How many backup tapes?  The data &#8220;landmines&#8221; of today could be greatly reduced by the Cloud as thin client technology becomes prevalent.  Small, temporary caches on handheld devices or Netbook computers pose less risk than transporting data buckets in the form of laptops.  Ask the CISO of any large company if all laptops have company &#8216;mandated&#8217; controls consistently applied; e.g. full disk encryption.  You&#8217;ll see the answer by looking at the whites of their eyes.  Despite best efforts around asset management and endpoint security we continue to see embarrassing and disturbing misses.  And what about SMBs?  How many use encryption for sensitive data, or even have a data classification policy in place?</li>
<li><strong>Monitoring benefits</strong>: central storage is easier to control and monitor.  The flipside is the nightmare scenario of <a href="http://www.gnucitizen.org/blog/most-attractive-targets-saas/">comprehensive data theft</a>.  However, I would rather spend my time as a security professional figuring out smart ways to protect and monitor access to data stored in one place (with the benefit of situational advantage) than trying to figure out all the places where the company data resides across a myriad of thick clients!  You can get the benefits of Thin Clients today but Cloud Storage provides a way to centralise the data faster and potentially cheaper.  The logistical challenge today is getting Terabytes of data to the Cloud in the first place.</li>
</ul>
<h4>2. Incident Response / Forensics</h4>
<ul>
<li><strong>Forensic readiness</strong>: with Infrastructure as a Service (IaaS) providers, I can build a dedicated forensic server in the same Cloud as my company and place it offline, ready for use when needed.  I would only need pay for storage until an incident happens and I need to bring it online.  I don&#8217;t need to call someone to bring it online or install some kind of remote boot software - I just click a button in the Cloud Providers web interface.  If I have multiple incident responders, I can give them a copy of the VM so we can distribute the forensic workload based on the job at hand or as new sources of evidence arise and need analysis.  To fully realise this benefit, commercial forensic software vendors would need to move away from archaic, physical dongle based licensing schemes to a network licensing model.</li>
<li><strong>Decrease evidence acquisition time</strong>: if a server in the Cloud gets compromised (i.e. broken into), I can now clone that server at the click of a mouse and make the cloned disks instantly available to my Cloud Forensics server.  I didn&#8217;t need to &#8220;find&#8221; storage or have it &#8220;ready, waiting and unused&#8221; - its just there.</li>
<li><strong>Eliminate or reduce service downtime</strong>: Note that in the above scenario I didn&#8217;t have to go tell the COO that the system needs to be taken offline for hours whilst I dig around in the RAID Array hoping that my physical acqusition toolkit is compatible (and that the version of RAID firmware isn&#8217;t supported by my forensic software).  Abstracting the hardware removes a barrier to even doing forensics in some situations.</li>
<li><strong>Decrease evidence transfer time</strong>: In the same Cloud, bit fot bit copies are super fast - made faster by that replicated, distributed filesystem my Cloud provider engineered for me.  From a network traffic perspective, it may even be free to make the copy in the same Cloud.  Without the Cloud, <strong>I </strong>would have to a lot of time consuming and expensive provisioning of physical devices.  I only pay for the storage as long as I need the evidence.</li>
<li><strong>Eliminate forensic image verification time</strong>: Some Cloud Storage implementations expose a cryptographic checksum or hash.  For example, Amazon S3 generates an MD5 hash <a href="http://docs.amazonwebservices.com/AmazonS3/2006-03-01/index.html?RESTObjectPUT.html">automagically</a> when you store an object.  In theory you no longer need to generate time-consuming MD5 checksums using external tools - its already there.</li>
<li><strong>Decrease time to access protected documents</strong>: Immense CPU power opens some doors.  Did the suspect password protect a document that is relevant to the investigation?  You can now test a wider range of candidate passwords in less time to speed investigations.</li>
</ul>
<h4>3. Password assurance testing (aka cracking)</h4>
<ul>
<li><strong>Decrease password cracking time</strong>: if your organisation regularly tests password strength by running password crackers you can use Cloud Compute to decrease crack time and you only pay for what you use.  Ironically, your cracking costs go up as people choose better passwords ;-).</li>
<li><strong>Keep cracking activities to dedicated machines</strong>: if today you use a distributed password cracker to spread the load across non-production machines, you can now put those agents in dedicated Compute instances - and thus stop mixing sensitive credentials with other workloads.</li>
</ul>
<h4>4. Logging</h4>
<ul>
<li><strong>&#8220;Unlimited&#8221;, pay per drink storage</strong>: logging is often an afterthought, consequently insufficient disk space is allocated and logging is either non-existant or minimal.  Cloud Storage changes all this - no more &#8216;guessing&#8217; how much storage you need for standard logs.</li>
<li><strong>Improve log indexing and search</strong>: with your logs in the Cloud you can leverage Cloud Compute to index those logs in real-time and get the benefit of <a href="http://blogs.splunk.com/thewilde/2008/06/24/splunk-ninja-inside-the-cloud/">instant search results.</a> What is different here?  The Compute instances can be plumbed in and scale as needed based on the logging load - meaning a true real-time view.</li>
<li><strong>Getting compliant with Extended logging</strong>: most modern operating systems offer extended logging in the form of a C2 audit trail.  This is rarely enabled for fear of performance degradation and log size.  Now you can &#8216;opt-in&#8217; easily - if you are willing to pay for the enhanced logging, you can do so.  Granular logging makes compliance and investigations easier.</li>
</ul>
<h4>5. Improve the state of security software (performance)</h4>
<ul>
<li><strong>Drive vendors to create more efficient security software</strong>: Billable CPU cycles get noticed.  More attention will be paid to inefficient processes; e.g. poorly tuned security agents.  Process accounting will make a comeback as customers target &#8216;expensive&#8217; processes.  Security vendors that understand how to squeeze the most performance from their software will win.</li>
</ul>
<h4>6. Secure builds</h4>
<ul>
<li><strong>Pre-hardened, change control builds</strong>: this is primarily a benefit of virtualization based Cloud Computing.  Now you get a chance to start &#8217;secure&#8217; (by your own definition) - you create your Gold Image VM and clone away.  There are ways to do this today with bare-metal OS installs but frequently these require additional 3rd party tools, are time consuming to clone or add yet another agent to each endpoint.</li>
<li><strong>Reduce exposure through patching offline</strong>: Gold images can be kept up securely kept up to date.  Offline VMs can be conveniently patched &#8220;off&#8221; the network.</li>
<li><strong>Easier to test impact of security changes</strong>: this is a big one.  Spin up a copy of your production environment, implement a security change and test the impact at low cost, with minimal startup time.  This is a big deal and removes a major barrier to &#8216;doing&#8217; security in production environments.</li>
</ul>
<h4>7. Security Testing</h4>
<ul>
<li><strong>Reduce cost of testing security: </strong>a SaaS provider only passes on a portion of their security testing costs.  By sharing the same application as a service, you don&#8217;t foot the expensive security code review and/or penetration test.  Even with Platform as a Service (PaaS) where your developers get to write code, there are potential cost economies of scale (particularly around use of code scanning tools that sweep source code for security weaknesses).</li>
</ul>
<h4>Your Thoughts?</h4>
<p>What benefits do you see that I haven&#8217;t included in the above list?  Where do you agree/disagree and importantly, why?</p>
<img src="http://feeds.feedburner.com/~r/CloudSecurity/~4/341289594" height="1" width="1"/>]]></content:encoded>
      <pubDate>Mon, 21 Jul 2008 03:00:15 +0000</pubDate>
      <category domain="http://securityratty.com/tag/benefits">benefits</category>
      <category domain="http://securityratty.com/tag/cloud">cloud</category>
      <category domain="http://securityratty.com/tag/security">security</category>
      <category domain="http://securityratty.com/tag/technical security benefits">technical security benefits</category>
      <category domain="http://securityratty.com/tag/based">based</category>
      <category domain="http://securityratty.com/tag/virtualization based cloud">virtualization based cloud</category>
      <category domain="http://securityratty.com/tag/efficient security software">efficient security software</category>
      <category domain="http://securityratty.com/tag/security software">security software</category>
      <category domain="http://securityratty.com/tag/cloud market">cloud market</category>
      <source url="http://feeds.feedburner.com/~r/CloudSecurity/~3/341289594/">Assessing the Security Benefits of Cloud Computing</source>
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    <item>
      <title><![CDATA[Man-in-the-Middle Attacks]]></title>
      <link>http://securityratty.com/article/4886f7013362b82e729992218c60dc53</link>
      <guid>http://securityratty.com/article/4886f7013362b82e729992218c60dc53</guid>
      <description><![CDATA[Last week's dramatic rescue of 15 hostages held by the guerrilla organization FARC was the result of months of intricate deception on the part of the Colombian government. At the center was a classic...]]></description>
      <content:encoded><![CDATA[Last week's dramatic rescue of 15 hostages held by the guerrilla organization FARC was the result of months of intricate deception on the part of the Colombian government. At the center was a classic man-in-the-middle attack.

In a man-in-the-middle attack, the attacker inserts himself between two communicating parties. Both believe they're talking to each other, and the attacker can delete or modify the communications at will. </p><p><cite>The Wall Street Journal</cite> reported how this <a href="http://online.wsj.com/article/SB121518490923829025.html">gambit played out in Colombia</a>: 

<blockquote>"The plan had a chance of working because, for months, in an operation one army officer likened to a 'broken telephone,' military intelligence had been able to convince Ms. Betancourt's captor, Gerardo Aguilar, a guerrilla known as 'Cesar,' that he was communicating with his top bosses in the guerrillas' seven-man secretariat. Army intelligence convinced top guerrilla leaders that they were talking to Cesar. In reality, both were talking to army intelligence."</blockquote>

This ploy worked because Cesar and his guerrilla bosses didn't know one another well. They didn't recognize one anothers' voices, and didn't have a friendship or shared history that could have tipped them off about the ruse. Man-in-the-middle is defeated by context, and the FARC guerrillas didn't have any.

And that's why man-in-the-middle, abbreviated MITM in the computer-security community, is such a problem online: Internet communication is often <a href="http://www.monkey.org/~dugsong/dsniff/">stripped of any context</a>. There's no way to <a href="http://www.oxid.it/">recognize someone's face</a>. There's no way to <a href="http://ettercap.sourceforge.net/">recognize someone's voice</a>. When you receive an e-mail purporting to come from a person or organization, you have no idea who actually sent it. When you visit a website, you have no idea if you're really visiting that website. We all like to pretend that we know who we're communicating with -- and for the most part, of course, there isn't any attacker inserting himself into our communications -- but in reality, we don't. And there are lots of <a href="http://sourceforge.net/projects/airjack/">hacker tools</a> that exploit this <a href="http://www.wsniff.com/">unjustified trust</a>, and <a href="http://www.theta44.org/karma/">implement MITM attacks</a>.

Even with context, it's still possible for MITM to fool both sides -- because electronic communications are often intermittent. Imagine that one of the FARC guerrillas became suspicious about who he was talking to. So he asks a question about their shared history as a test: "What did we have for dinner that time last year?" or something like that. On the telephone, the attacker wouldn't be able to answer quickly, so his ruse would be discovered.  But e-mail conversation isn't synchronous. The attacker could simply pass that question through to the other end of the communications, and when he got the answer back, he would be able to reply.

This is the way MITM attacks work against web-based financial systems. A bank demands authentication from the user: a password, a one-time code from a token or whatever. The attacker sitting in the middle receives the request from the bank and passes it to the user.  The user responds to the attacker, who passes that response to the bank. Now the bank assumes it is talking to the legitimate user, and the attacker is free to send transactions directly to the bank. This kind of attack completely bypasses any <a href="http://www.schneier.com/crypto-gram-0503.html#2">two-factor authentication mechanisms</a>, and is becoming a more popular identity-theft tactic.

There are cryptographic solutions to MITM attacks, and there are secure web protocols that implement them. Many of them require shared secrets, though, making them useful only in situations where people already know and trust one another.

The NSA-designed <a href="http://www.fas.org/irp/program/security/_work/stu3.html">STU-III and STE</a> secure telephones solve the MITM problem by embedding the identity of each phone together with its key. (The NSA creates all keys and is trusted by everyone, so this works.) When two phones talk to each other securely, they exchange keys and display the other phone's identity on a screen. Because the phone is in a secure location, the user now knows who he is talking to, and if the phone displays another organization -- as it would if there were a MITM attack in progress -- he should hang up.

Zfone, a <a href="http://zfoneproject.com/faq.html#mitm">secure VoIP system</a>, protects against MITM attacks with a short authentication string. After two Zfone terminals exchange keys, both computers display a four-character string. The users are supposed to manually verify that both strings are the same -- "my screen says 5C19; what does yours say?" -- to ensure that the phones are communicating directly with each other and not with an MITM. The <a href="http://www.flickr.com/photos/21746901@N08/2275723713/">AT&T TSD-3600</a> worked similarly.

This sort of protection is embedded in SSL, although no one uses it. As it is normally used, SSL provides an encrypted communications link to whoever is at the other end: bank and phishing site alike. And the better phishing sites create valid SSL connections, so as to more effectively fool users. But if the user wanted to, he could manually <a href="http://www.microsoft.com/protect/yourself/phishing/spoof.mspx">check the SSL certificate</a> to see if it was issued to "National Bank of Trustworthiness" or "Two Guys With a Computer in Nigeria."  
 
No one does, though, because you have to both remember and be willing to do the work. (The browsers could make this easier if they wanted to, but they don’t seem to want to.) In the real world, you can easily tell a branch of your bank from a money changer on a street corner. But on the internet, a phishing site can be easily made to look like your bank's legitimate website. Any method of telling the two apart takes work. And that's the first step to fooling you with a MITM attack.
 
Man-in-the-middle isn't new, and it doesn't have to be technological. But the internet makes the attacks easier and more powerful, and that's not going to change anytime soon.

This essay <a href="http://www.wired.com/politics/security/commentary/securitymatters/2008/07/securitymatters_0710">originally appeared</a> on Wired.com.<div class="feedflare">
<a href="http://feeds.feedburner.com/~f/schneier/fulltext?a=bCKMKJ"><img src="http://feeds.feedburner.com/~f/schneier/fulltext?i=bCKMKJ" border="0"></img></a> <a href="http://feeds.feedburner.com/~f/schneier/fulltext?a=1NNFNJ"><img src="http://feeds.feedburner.com/~f/schneier/fulltext?i=1NNFNJ" border="0"></img></a>
</div>]]></content:encoded>
      <pubDate>Tue, 15 Jul 2008 02:47:19 +0000</pubDate>
      <category domain="http://securityratty.com/tag/implement mitm attacks">implement mitm attacks</category>
      <category domain="http://securityratty.com/tag/implement">implement</category>
      <category domain="http://securityratty.com/tag/mitm attacks">mitm attacks</category>
      <category domain="http://securityratty.com/tag/mitm">mitm</category>
      <category domain="http://securityratty.com/tag/mitm attack">mitm attack</category>
      <category domain="http://securityratty.com/tag/bank">bank</category>
      <category domain="http://securityratty.com/tag/bank demands authentication">bank demands authentication</category>
      <category domain="http://securityratty.com/tag/bank assumes">bank assumes</category>
      <category domain="http://securityratty.com/tag/attacker inserts">attacker inserts</category>
      <source url="http://www.schneier.com/blog/archives/2008/07/maninthemiddle_1.html">Man-in-the-Middle Attacks</source>
    </item>
    <item>
      <title><![CDATA[Thales buys nCipher for $100 million]]></title>
      <link>http://securityratty.com/article/a48e91374472d886782fb007eb49f0c7</link>
      <guid>http://securityratty.com/article/a48e91374472d886782fb007eb49f0c7</guid>
      <description><![CDATA[Thales U.K. has reached an agreement to buy cryptographic security vendor nCipher for 50.7 million (US$100.3 million), the two companies announced...]]></description>
      <content:encoded><![CDATA[Thales U.K. has reached an agreement to buy cryptographic security vendor nCipher for £50.7 million (US$100.3 million), the two companies announced Friday.]]></content:encoded>
      <pubDate>Thu, 10 Jul 2008 20:00:00 +0000</pubDate>
      <category domain="http://securityratty.com/tag/million">million</category>
      <category domain="http://securityratty.com/tag/thales">thales</category>
      <category domain="http://securityratty.com/tag/friday">friday</category>
      <category domain="http://securityratty.com/tag/companies">companies</category>
      <category domain="http://securityratty.com/tag/us100">us100</category>
      <category domain="http://securityratty.com/tag/agreement">agreement</category>
      <source url="http://www.networkworld.com/news/2008/071108-thales-buys-ncipher-for-100.html?fsrc=rss-security">Thales buys nCipher for $100 million</source>
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