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    <title><![CDATA[[SecurityRatty] tag: wpa2]]></title>
    <link>http://securityratty.com/tag/wpa2</link>
    <description></description>
    <pubDate>Tue, 16 Oct 2007 03:08:58 +0000</pubDate>
    <generator>iRatty Engine</generator>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <item>
      <title><![CDATA[Battered, but not broken: understanding the WPA crack]]></title>
      <link>http://securityratty.com/article/0948305edc58ad33ec282619217522a3</link>
      <guid>http://securityratty.com/article/0948305edc58ad33ec282619217522a3</guid>
      <description><![CDATA[WiFi security takes a hit with the disclosure of an effective exploit for small packets encrypted with the TKIP flavor of WiFi Protected Access. The technique is fiendishly clever; the security...]]></description>
      <content:encoded><![CDATA[WiFi security takes a hit with the disclosure of an effective exploit for small packets encrypted with the TKIP flavor of WiFi Protected Access. The technique is fiendishly clever; the security solution, simple: switch to AES-only in WPA2.<img src="http://feedproxy.google.com/~r/digg/topic/security/popular/~4/HCkWOreqU_0" height="1" width="1"/>]]></content:encoded>
      <pubDate>Fri, 07 Nov 2008 15:30:03 +0000</pubDate>
      <category domain="http://securityratty.com/tag/wifi security takes">wifi security takes</category>
      <category domain="http://securityratty.com/tag/wifi">wifi</category>
      <category domain="http://securityratty.com/tag/tkip flavor">tkip flavor</category>
      <category domain="http://securityratty.com/tag/fiendishly clever">fiendishly clever</category>
      <category domain="http://securityratty.com/tag/security solution">security solution</category>
      <category domain="http://securityratty.com/tag/effective exploit">effective exploit</category>
      <category domain="http://securityratty.com/tag/access">access</category>
      <category domain="http://securityratty.com/tag/technique">technique</category>
      <category domain="http://securityratty.com/tag/packets">packets</category>
      <source url="http://feeds.digg.com/~r/digg/topic/security/popular/~3/HCkWOreqU_0/Battered_but_not_broken_understanding_the_WPA_crack">Battered, but not broken: understanding the WPA crack</source>
    </item>
    <item>
      <title><![CDATA[Debunking the Latest Fear Mongering News on WPA security]]></title>
      <link>http://securityratty.com/article/db5c2f6d20bfbc204064e7ebc539557c</link>
      <guid>http://securityratty.com/article/db5c2f6d20bfbc204064e7ebc539557c</guid>
      <description><![CDATA[I had been meaning to write about recent exaggerated claims that WPA security had been hacked, but George Ou beat me to it . The buzz comes from Elcomsoft's Distributed Password Recovery . The...]]></description>
      <content:encoded><![CDATA[I had been meaning to write about recent exaggerated claims that WPA security had been hacked, but <a href="http://www.formortals.com/Home/tabid/36/EntryID/119/Default.aspx">George Ou beat me to it</a>.

The buzz comes from <a href="http://www.elcomsoft.com/edpr.html">Elcomsoft's Distributed Password Recovery</a>. The innovation is that they use NVIDIA GPU acceleration for password cracking and can distribute the crack across a network to multiple clients and their NVIDIA GPUs. The GPU acceleration, they claim, "reduces password recovery time by a factor of 20."

They also take the unfortunate approach, <a href="http://www.elcomsoft.com/PR/edpr_081009_en.pdf">in a press release</a>, of massive gains in cracking WPA and WPA2 protection, and that they can "...break Wi-Fi encryption up to 100 times faster than by using CPU only."

100 times! 2 orders of magnitude! That must be a lot, right? Well, probably not. This is where George Ou calls shenanigans.

First, he points out that this only affects password protection systems that rely on password complexity, and that, as a general rule, the time involved is proportional to the complexity of the password. So if your password would normally take a million years to crack, it would take 10,000 years with this system. Draw your own conclusions.

He also points out, just to get past the WPA buzzwordism, that this is a more general attack mechanism and could, for example, be used against certain VPN systems.

With respect to WPA/WPA2 specifically, the attack is generally useful only against home users, because they are generally the ones using PSK (Private Shared Key) authentication. "It has zero affect enterprise mode WPA deployments which use TLS protected authentication such as PEAP or EAP-TLS. Internal LAN authentication schemes such as NTLM and LDAP are also significantly weakened.  SSL authentication schemes are not vulnerable to this particular attack."

If you are relying on password complexity for protection then his advice, and mine, is old news: first, if you're a business, perhaps you should be using a TLS-based authentication system. Also, you should make sure that your passwords are sufficiently complex and changed often enough. Ou has some specific advice about this in his column, but as he says, there are usually easier ways to get passwords (like offering people chocolate for them) than to spend years cracking them with thousands of dollars of computing power.
<p><a href="http://feedads.googleadservices.com/~a/OvpRctfZEnjDyyEg3MByesn2KpY/a"><img src="http://feedads.googleadservices.com/~a/OvpRctfZEnjDyyEg3MByesn2KpY/i" border="0" ismap="true"></img></a></p><img src="http://feedproxy.google.com/~r/RSS/cheap_hack/~4/zhaPa_33ZEQ" height="1" width="1"/>]]></content:encoded>
      <pubDate>Mon, 13 Oct 2008 05:07:51 +0000</pubDate>
      <category domain="http://securityratty.com/tag/wpa">wpa</category>
      <category domain="http://securityratty.com/tag/password">password</category>
      <category domain="http://securityratty.com/tag/password recovery">password recovery</category>
      <category domain="http://securityratty.com/tag/password complexity">password complexity</category>
      <category domain="http://securityratty.com/tag/authentication">authentication</category>
      <category domain="http://securityratty.com/tag/authentication system">authentication system</category>
      <category domain="http://securityratty.com/tag/complexity">complexity</category>
      <category domain="http://securityratty.com/tag/wpa security">wpa security</category>
      <category domain="http://securityratty.com/tag/nvidia gpu acceleration">nvidia gpu acceleration</category>
      <source url="http://feeds.ziffdavisenterprise.com/~r/RSS/cheap_hack/~3/zhaPa_33ZEQ/debunking_the_latest_fear_mongering_news_on_wpa_security.html">Debunking the Latest Fear Mongering News on WPA security</source>
    </item>
    <item>
      <title><![CDATA[Wee-Fi: Houston-Fi, ASCII WPA Passphrases, Green Wi-Fi]]></title>
      <link>http://securityratty.com/article/7f30d96346f66d41619e4abd9bae8e7d</link>
      <guid>http://securityratty.com/article/7f30d96346f66d41619e4abd9bae8e7d</guid>
      <description><![CDATA[Houston flips switch on free downtown Wi-Fi: Dwight Silverman of the Houston Chronicle accidentally discovers the soft launch of the network funded by EarthLink's $5m default fee. (The fee was paid...]]></description>
      <content:encoded><![CDATA[<p><img src="http://wifinetnews.com/images/weefi.jpg" align="right" border="0" hspace="5" /><a href="http://blogs.chron.com/techblog/archives/2008/08/it_lives_city_of_houston_turns_on_free_downto.html"><strong>Houston flips switch on free downtown Wi-Fi:</strong></a> Dwight Silverman of the Houston Chronicle accidentally discovers the soft launch of the network funded by EarthLink's $5m default fee. (The fee was paid when they missed a milestone, and the firm later walked away.) The downtown area now has a limited pilot project that's free; the real effort in Houston is supposed to be at 10 housing projects and in parks where service would be used to bridge the digital divide and improve the quality of life. How, exactly, is part of what's being tested.</p>

<p><a href="http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2008/08/18/MNH312BTS1.DTL&hw=wi+fi&sn=004&sc=589"><strong>That's ASCII, not hex:</strong></a> An article on wardriving raises security hackles by repeating some slightly overheated statements about Wi-Fi security. The article opens with a 63-character ASCII WPA passphrase, which is later described as "hex." (ASCII passphrases in WPA can be up to 63 "printable" characters - ASCII 32 to 127 - while a hex version of a 256-bit TKIP or AES password is 64 hexadecimal digits long.) The article tries to conflate Wi-Fi attacks that led to the largest set of breaches in retail credit-card systems and wardriving, a hobbyist activity that's never been looked on very favorably by law enforcement. The sense of ennui of wardriving pioneers is pretty clear; when Wi-Fi is everywhere and generally secured, it's far less interesting. The wardriver in the article convinced the reporter that a maximum-length WPA passphrase stored on a USB drive for automatic use was the best way to go. But, really, 20 characters containing letters and punctuation and no words found in a dictionary along with changing your network's SSID (network name) provides all the security you'll ever need for a home or small business. (If you need more, deploy WPA/WPA2 Personal.)</p>

<p><a href="http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2008/08/16/BUA712BH1O.DTL&hw=wi+fi&sn=001&sc=1000"><strong>Green Wi-Fi's Senegal efforts hit snags:</strong></a> The folks at Green Wi-Fi are well motivated, and they're running up against all forms of security theater and bureaucracy both here and in Senegal, where they have an active project. The San Francisco Chronicle notes the group's effort to build solar-powered, self-sustaining Internet access via mesh networked nodes. Getting devices out of the country, clearing customs in Senegal, and hooking up their solar system all hit problems they're working through. As with the One Laptop Per Child program, I see a "build it and they will come" mentality in <a href="http://www.green-wifi.org/"><strong>Green Wi-Fi's mission statement</strong></a>: the notion that providing computing power and Internet access will result in good things, rather than an effort to figure out what good things need to be achieved, and whether computers and the Internet will assist. </p>]]></content:encoded>
      <pubDate>Tue, 19 Aug 2008 06:26:25 +0000</pubDate>
      <category domain="http://securityratty.com/tag/wi-fi">wi-fi</category>
      <category domain="http://securityratty.com/tag/wi-fi attacks">wi-fi attacks</category>
      <category domain="http://securityratty.com/tag/houston">houston</category>
      <category domain="http://securityratty.com/tag/wi-fi security">wi-fi security</category>
      <category domain="http://securityratty.com/tag/free downtown wi-fi">free downtown wi-fi</category>
      <category domain="http://securityratty.com/tag/free">free</category>
      <category domain="http://securityratty.com/tag/security">security</category>
      <category domain="http://securityratty.com/tag/ascii">ascii</category>
      <category domain="http://securityratty.com/tag/security theater">security theater</category>
      <source url="http://wifinetnews.com/archives/008423.html">Wee-Fi: Houston-Fi, ASCII WPA Passphrases, Green Wi-Fi</source>
    </item>
    <item>
      <title><![CDATA[iPhone 2.0 Software Adds 802.1X for Enterprises]]></title>
      <link>http://securityratty.com/article/3f84bfe0c234391eca261e2bbfb26e83</link>
      <guid>http://securityratty.com/article/3f84bfe0c234391eca261e2bbfb26e83</guid>
      <description><![CDATA[Apple adds secure enterprise logins for iPhone: The iPhone 2.0 software, available through a download link for existing 2G iPhones today, adds promised support for the 802.1X port-based authentication...]]></description>
      <content:encoded><![CDATA[<p><strong>Apple adds secure enterprise logins for iPhone:</strong> The iPhone 2.0 software, available through a download link for existing 2G iPhones today, adds promised support for the 802.1X port-based authentication required in any company that's even remotely serious about its network security. 802.1X isolates connecting to an access point from gaining access to the network to which the access point is connected. A special client, known as a supplicant, must provide the right credentials for a device to be approved for access. Cryptography binds the process. (Instructions for manually installing the software <a href="http://blog.wired.com/gadgets/2008/07/how-to-get-the.html"><strong>are over at Wired</strong></a>. The update will likely be pushed out via iTunes to current owners tomorrow, and is included on the iPhone 3G, which goes on sale starting today over the international dateline and tomorrow in the U.S., Europe, and elsewhere.)</p>

<p><img src="http://wifinetnews.com//images/2008/wpa_enterprise_iphone.jpg" alt="wpa_enterprise_iphone.jpg" border="0" width="160" height="240" align="right" /> Apple splits its 802.1X support into two pieces. There's basic support built into the iPhone 2.0 software, found in the Settings application's Wi-Fi section. Click Other. Click the None label next to Security, and the WPA Enterprise and WPA2Enterprise options appear. Select either, and the main login screen lets you enter the network's name (SSID), a user name, and a password. This basic method is limited to WPA Enterprise and WPA2 Enterprise, the two most common (and most secure) forms of 802.1X.</p>

<p>Most enterprises will want much more control over this process, and Apple provides the <a href="http://www.apple.com/support/downloads/"><strong>iPhone Configuration Utility</strong></a>, currently available in its most complete form only as a Mac OS X application, and in more limited forms as Web 2.0 applications for Windows and Mac OS X.</p>

<p>The utility serves two purposes: creating configuration profiles, including for multiple Wi-Fi networks and VPN connections; and allowing iPhones in an enterprise to run internally developed iPhone software. The Wi-Fi profiles allow you to create WEP or WPA/WPA2 802.1X configurations, and include support for choosing allowed EAP messaging types, configuring authentication elements associated with a given EAP type, and adding server certificates and names for better authentication control. </p>

<p><img src="http://wifinetnews.com//images/2008/iphone_wifi_prov_proto.jpg" alt="iphone_wifi_prov_proto.jpg" border="0" width="406" height="437" style="border: 1px solid #030000;" /></p>

<p>Once created, these profiles can be distributed throughout a company via email or as a direct download to the iPhone via an intranet Web server. Apple chose not to encrypt them, which means that certain information that's not secured--such as the shared secret for certain VPN connections--could be disclosed to someone who had access to the profile or could download it off the local network. </p>]]></content:encoded>
      <pubDate>Thu, 10 Jul 2008 11:51:30 +0000</pubDate>
      <category domain="http://securityratty.com/tag/software">software</category>
      <category domain="http://securityratty.com/tag/iphone">iphone</category>
      <category domain="http://securityratty.com/tag/iphone software">iphone software</category>
      <category domain="http://securityratty.com/tag/enterprise">enterprise</category>
      <category domain="http://securityratty.com/tag/wpa2 enterprise">wpa2 enterprise</category>
      <category domain="http://securityratty.com/tag/wpa enterprise">wpa enterprise</category>
      <category domain="http://securityratty.com/tag/iphone configuration utility">iphone configuration utility</category>
      <category domain="http://securityratty.com/tag/network security">network security</category>
      <category domain="http://securityratty.com/tag/network">network</category>
      <source url="http://wifinetnews.com/archives/008391.html">iPhone 2.0 Software Adds 802.1X for Enterprises</source>
    </item>
    <item>
      <title><![CDATA[San Quentin visitor and volunteer information lost]]></title>
      <link>http://securityratty.com/article/dbf873f6918086b574c9b46d905b6061</link>
      <guid>http://securityratty.com/article/dbf873f6918086b574c9b46d905b6061</guid>
      <description><![CDATA[Technorati Tag: Security Breach

Date Reported
3/29/08

Organization
State of California

Contractor/Consultant/Branch
Department of Corrections and Rehabilitation
San Quentin State Prison

Victims...]]></description>
      <content:encoded><![CDATA[Technorati Tag: <a href="http://technorati.com/tag/security+breach" rel="tag">Security Breach</a><br><br>
<img src="http://breachblog.com/images/95781-88451/caldoc.jpg" align="right" height="162" width="162"><font size="2"><span style="font-weight: bold;">Date Reported: </span><br>3/29/08<br><br><span style="font-weight: bold;">Organization: </span><br><a href="http://www.ca.gov/">State of California</a> <br><br><span style="font-weight: bold;">Contractor/Consultant/Branch:</span><br><a href="http://www.cdcr.ca.gov/index.html">Department of Corrections and Rehabilitation</a> <br><a href="http://www.cdcr.ca.gov/Visitors/Facilities/SQ.html">San Quentin State Prison</a> <br><br><span style="font-weight: bold;">Victims:</span><br>Volunteers and visitors<br><br><span style="font-weight: bold;">Number Affected:</span><br>3,500+<br><br><span style="font-weight: bold;">Types of Data:</span><br>"names, birth dates and driver's license numbers"<br><br><span style="font-weight: bold;">Breach Description:</span><br>"A flash memory drive containing names, birth dates and driver's license numbers of more than 3,500 people who either volunteered or visited San Quentin State Prison in a group tour has been lost, a prison official said Friday."<br><br><span style="font-weight: bold;">Reference URL:</span><br><a href="http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2008/03/29/BA4KVSJ9O.DTL">The San Francisco Chronicle</a> <br><a href="http://www.kcbs.com/Personal-Information-of-Prison-Visitors-Missing/1909845">KCBS 740 AM News</a> <br><br><span style="font-weight: bold;">Report Credit:</span><br>Matthew Yi, The San Francisco Chronicle<br><br><span style="font-weight: bold;">Response:</span><br>From the online sources cited above:<br><br>A flash memory drive containing names, birth dates and driver's license numbers of more than 3,500 people who either volunteered or visited San Quentin State Prison in a group tour has been lost, a prison official said Friday.<br><br>The flash drive was used to move the data each evening from the prison's administrative office near the parking lot to computers at the two entrance gates to the facility to allow guards to identify volunteers or groups, such as college students, that tour the prison, said Samuel Robinson, a San Quentin spokesman.<br><span style="font-style: italic;">[Evan] Huh?&nbsp; How about a network employing encryption?&nbsp; They have this new technology called WPA2 (</span><a style="font-style: italic;" href="http://www.wi-fi.org/knowledge_center/wpa2">Wi-Fi Protected Access 2</a><span style="font-style: italic;">).&nbsp; It would be much more efficient, secure and cost effective to network this securely.</span><br><br>"What happens is that we have to transport that information out to individual areas where we let people through" onto prison grounds, he said. "It's our security measure to walk the flash drive."<br><br>The flash drive did not contain Social Security numbers, but the personal information on visitors was not encrypted, he said, adding that the prison has since decided to encrypt the data.<br><span style="font-style: italic;">[Evan] It's too bad that it took a breach before prison officials noticed the risk of carrying confidential information on unencrypted mobile devices.&nbsp; Going forward this is a good decision by the prison, but this is what we call "reactive security".</span><br><br>Prison officials have not received any reports of identify theft tied to this incident<br><br>Sen. Gloria Romero, D-Los Angeles, chairwoman of the Senate Public Safety Committee, criticized the Corrections Department for losing such sensitive information, and said she will call prisons secretary James Tilton to address the issue.<br><br>"This is how cavalier the Corrections Department can be with private information," she said. "There has been a breach of security."<br><br>The unit was discovered missing March 4 and a preliminary investigation shows that it was last used on March 3, Robinson said. It's yet unclear how the flash drive was lost or if it may be somewhere on prison grounds, he said. There is no indication that the flash drive was stolen for malicious reasons, such as identity theft<br><br>Prison officials recently sent out letters alerting the individuals whose information is believed to be on the flash drive.<br><br>Anyone who has visited San Quentin and is concerned their personal information could be on the flash drive may call Sgt. Rudy Luna, administrative assistant, at (415) 455-5000 or Laura Bowman, community partnership manager, at (415) 454-1460, extension 5400.<br><br><span style="font-weight: bold;">Commentary:</span><br>Thankfully, the flash drive did not contain Social Security numbers.&nbsp; Can names, addresses and driver's license numbers be used for identity theft, directly?<br><br>Carrying confidential information on mobile devices is risky.&nbsp; Not encrypting it is reckless.<br><br><span style="font-weight: bold;">Past Breaches:</span><br>Unknown</font>
<br>
<script src="http://feeds.feedburner.com/%7Es/breachblog?i=http://breachblog.com/2008/03/31/caldoc.aspx" type="text/javascript" charset="utf-8"></script>]]></content:encoded>
      <pubDate>Mon, 31 Mar 2008 07:14:31 +0000</pubDate>
      <category domain="http://securityratty.com/tag/prison official">prison official</category>
      <category domain="http://securityratty.com/tag/prison">prison</category>
      <category domain="http://securityratty.com/tag/information">information</category>
      <category domain="http://securityratty.com/tag/prison officials">prison officials</category>
      <category domain="http://securityratty.com/tag/san quentin">san quentin</category>
      <category domain="http://securityratty.com/tag/prison officials recently">prison officials recently</category>
      <category domain="http://securityratty.com/tag/flash drive">flash drive</category>
      <category domain="http://securityratty.com/tag/breach description">breach description</category>
      <category domain="http://securityratty.com/tag/breach">breach</category>
      <source url="http://breachblog.com/2008/03/31/caldoc.aspx">San Quentin visitor and volunteer information lost</source>
    </item>
    <item>
      <title><![CDATA[Wireless security foiled by new exploits]]></title>
      <link>http://securityratty.com/article/46701b4612884468026831937dedb4a3</link>
      <guid>http://securityratty.com/article/46701b4612884468026831937dedb4a3</guid>
      <description><![CDATA[Just when you thought your wireless network was locked down, a whole new set of exploits and hacker tools hits. WPA2, PEAP, TTLS or EAP/TLS can shore up your network, if configured properly. Securing...]]></description>
      <content:encoded><![CDATA[Just when you thought your wireless network was locked down, a whole new set of exploits and hacker tools hits. WPA2, PEAP, TTLS or EAP/TLS can shore up your network, if configured properly. Securing clients is a lot more difficult. These topics and more were addressed by Joshua Wright in this recent Network World chat. Wright is famous for his irreverent security blog WillHackforSushi.com. He is also the author of the six-day SANS Institute course, Assessing and Securing Wireless Networks. Plus he's a popular speaker at a long list of security conferences.]]></content:encoded>
      <pubDate>Mon, 25 Feb 2008 21:00:00 +0000</pubDate>
      <category domain="http://securityratty.com/tag/network">network</category>
      <category domain="http://securityratty.com/tag/joshua wright">joshua wright</category>
      <category domain="http://securityratty.com/tag/wright">wright</category>
      <category domain="http://securityratty.com/tag/six-day sans institute">six-day sans institute</category>
      <category domain="http://securityratty.com/tag/wireless network">wireless network</category>
      <category domain="http://securityratty.com/tag/irreverent security blog">irreverent security blog</category>
      <category domain="http://securityratty.com/tag/hacker tools hits">hacker tools hits</category>
      <category domain="http://securityratty.com/tag/security conferences">security conferences</category>
      <category domain="http://securityratty.com/tag/popular speaker">popular speaker</category>
      <source url="http://www.networkworld.com/chat/archive/2008/022608-josh-wright-wireless-security-chat.html?fsrc=rss-security">Wireless security foiled by new exploits</source>
    </item>
    <item>
      <title><![CDATA[Myth vs. reality: Wireless SSIDs]]></title>
      <link>http://securityratty.com/article/4a91fb214b08b79f9031eb1b8995f6ef</link>
      <guid>http://securityratty.com/article/4a91fb214b08b79f9031eb1b8995f6ef</guid>
      <description><![CDATA[Do you ever wonder sometimes how it is that some ideas just won't die? Like the thought that not broadcasting your wireless network's SSID will somehow make you more secure? This is a myth that needs...]]></description>
      <content:encoded><![CDATA[<p>Do you ever wonder sometimes how it is that some ideas just won't die? Like the thought that not broadcasting your wireless network's SSID will somehow make you more secure? This is a <a href="http://www.microsoft.com/technet/technetmag/issues/2005/11/SecurityWatch/" target="_blank">myth</a> that needs to be forcibly dragged out behind the woodshed, strangled until it wheezes its last labored breath, then shot several times for good measure.</p> <p>Folks, there are fundamental differences between names, which are public claims of identities, and authenticators, which are secrets used to prove identities, and I've <a href="http://www.microsoft.com/technet/community/columns/secmgmt/sm0206.mspx" target="_blank">written extensively about this before</a>. <strong>An SSID is a network name</strong>, <em>not</em> -- I repeat, <em>not</em> -- a password. A wireless network has an SSID to distinguish it from other wireless networks in the vicinity. <strong>The SSID was never designed to be hidden</strong>, and therefore won't provide your network with any kind of protection if you try to hide it. It's a violation of the <a href="http://standards.ieee.org/getieee802/802.11.html" target="_blank">802.11 specification</a> to keep your SSID hidden; the 802.11i specification amendment (which defines WPA2, discussed later) even states that a computer can refuse to communicate with an access point that doesn't broadcast its SSID. And, even if you think your SSID is hidden, it really isn't. Let me explain.</p> <p>All 802.11 wireless networks, regardless of the kind of operating system or encryption you might use, also emit unencrypted frames at times. One kind of unencrypted frame is an <em>association frame.</em> This is what a client computer, or "supplicant" in the 802.11 protocol vernacular, emits when it wants to join a wireless network. Contained within the frame, in clear text of course (since the frame is unencrypted), is the SSID of the network the supplicant wants to join.</p> <p>Both Windows XP and Vista work best when your access points broadcast their SSIDs. XP really <a href="http://support.microsoft.com/kb/811427" target="_blank">doesn't behave well at all</a> with nonbroadcasting SSIDs. Vista has some <a href="http://support.microsoft.com/kb/929661" target="_blank">added smarts to improve this</a> a bit. Normally, Vista continually sends probe requests for nonbroadcasting networks. These probes are similar to unencrypted 802.11 association frames, and will generate clear-text responses from the access points if a nonbroadcasting network is present. You can reduce, but not entirely eliminate, these probes by configuring the wireless client to probe only for automatically-connected nonbroadcasting networks.</p> <p>Both these behaviors make it very easy for an attacker to discover your SSID. The bad guy, perhaps a contractor or a guest in your facility, could run one of many wireless sniffer programs and simply capture the hundreds of association frames or probes that litter your air. No amount of "hiding" configured in your access points can prevent this kind of traffic interception.</p> <p>So there you have it, simple SSID discovery. The old axiom remains true: security by obscurity is no security at all. Hiding an SSID will not hide a wireless network, so ignore any such advice -- and it's amazing how often I continue to see this. By the way, <strong>also ignore any advice that says to use MAC address filtering</strong>. It's amazingly trivial to spoof the MAC address of an allowed supplicant -- simply sniff the traffic, look at the MAC addresses, and use the neat little <a href="http://www.klcconsulting.net/smac" target="_blank">SMAC utility</a> to change your MAC to one that's permitted.</p> <p><a href="http://technet.microsoft.com/en-us/library/bb726942.aspx" target="_blank">Nonbroadcasting networks are not secure networks</a>. The right way to secure a wireless network is to use protocols that are designed specifically to address wireless network threats. If you're still using WEP, either static or dynamic, I encourage you to move to WPA2 as soon as possible. For those of you at home running XP and have kept it updated, or if you're running Vista, then, you simply need to <a href="http://www.microsoft.com/technet/community/columns/cableguy/cg0505.mspx" target="_blank">enable WPA2</a>. We've got some additional guidance for <a href="http://www.microsoft.com/downloads/details.aspx?familyid=269902e8-fc41-4eb1-9374-44612e64f0fb&amp;displaylang=en" target="_blank">home/small offices</a> and for enterprise networks <a href="http://www.microsoft.com/downloads/details.aspx?familyid=cdb639b3-010b-47e7-b234-a27cda291dad&amp;displaylang=en" target="_blank">with certificate services</a> or <a href="http://www.microsoft.com/downloads/details.aspx?familyid=60c5d0a1-9820-480e-aa38-63485eca8b9b&amp;displaylang=en" target="_blank">without</a>. If you have hardware that's more than two years old and you can't upgrade it, check to see whether it supports WPA (an interim specification released before WPA2 was ratified). Both WPA and WPA2 are built on sound cryptographic principles, they're proven in the field, and they'll keep the bad guys out -- even when you're broadcasting your SSID to the world.</p><img src="http://blogs.technet.com/aggbug.aspx?PostID=2181282" width="1" height="1">]]></content:encoded>
      <pubDate>Tue, 16 Oct 2007 03:08:58 +0000</pubDate>
      <category domain="http://securityratty.com/tag/simple ssid discovery">simple ssid discovery</category>
      <category domain="http://securityratty.com/tag/network">network</category>
      <category domain="http://securityratty.com/tag/ssid">ssid</category>
      <category domain="http://securityratty.com/tag/wireless network">wireless network</category>
      <category domain="http://securityratty.com/tag/networks">networks</category>
      <category domain="http://securityratty.com/tag/enterprise networks">enterprise networks</category>
      <category domain="http://securityratty.com/tag/wireless networks">wireless networks</category>
      <category domain="http://securityratty.com/tag/mac">mac</category>
      <category domain="http://securityratty.com/tag/secure networks">secure networks</category>
      <source url="http://blogs.technet.com/steriley/archive/2007/10/16/myth-vs-reality-wireless-ssids.aspx">Myth vs. reality: Wireless SSIDs</source>
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