Hack The Sec-Leading Resource Of Linux Tutorial: Kernel Hacker

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<span style="color: #0b5394; font-family: Verdana, sans-serif; font-size: large;"><b>Zero-Day Flaw Found in 'Linux Kernel' leaves Millions Vulnerable</b></span><br />
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A new critical zero-day vulnerability has been discovered in the<b style="border: 0px; font-family: inherit; font-size: inherit; font-stretch: inherit; font-style: inherit; font-variant: inherit; line-height: inherit; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"> Linux kernel </b>that could allow attackers to gain root level privileges by running a malicious Android or Linux application on an affected device.</div>
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<br style="content: ' '; display: block; margin: 20px 0px 0px; outline: 0px; padding: 0px;" />The critical Linux kernel flaw (<a href="http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=2016-0728" rel="nofollow" style="border: 0px; color: #1177b8; font-family: inherit; font-size: inherit; font-stretch: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; margin: 0px; outline: none; padding: 0px; text-decoration: none; vertical-align: baseline;" target="_blank">CVE-2016-0728</a>) has been identified by a group of researchers at a startup named Perception Point.</div>
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The vulnerability was present in the code since 2012, and affects any operating system with <b style="border: 0px; font-family: inherit; font-size: inherit; font-stretch: inherit; font-style: inherit; font-variant: inherit; line-height: inherit; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Linux kernel 3.8 and higher</b>, so there are probably tens of millions of computers, both 32-bit and 64-bit, exposed to this flaw.</div>
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However, the most bothersome part is that the problem affects <b style="border: 0px; font-family: inherit; font-size: inherit; font-stretch: inherit; font-style: inherit; font-variant: inherit; line-height: inherit; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Android versions KitKat and higher</b>, which means about 66 percent of all Android devices are also exposed to the serious Linux kernel flaw.</div>
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Impact of the Zero-Day Vulnerability</h3>
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An attacker would only require local access to exploit the flaw on a Linux server.</div>
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If successfully exploited, the vulnerability can allow attackers to get root access to the operating system, enabling them to delete files, view private information, and install malicious apps.</div>
<blockquote class="tr_bq" style="border-left-color: rgb(232, 232, 232); border-left-style: solid; border-width: 0px 0px 0px 5px; font-stretch: inherit; margin: 0px; outline: 0px; padding: 10px; quotes: none; vertical-align: baseline;">
<i style="border: 0px; font-family: inherit; font-size: inherit; font-stretch: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">"It's pretty bad because a user with legitimate or lower privileges can gain root access and compromise the whole machine," </i><b style="border: 0px; font-family: inherit; font-size: inherit; font-stretch: inherit; font-style: inherit; font-variant: inherit; line-height: inherit; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Yevgeny Pats</b>, co-founder and CEO at security vendor Perception Point, said in a <a href="http://perception-point.io/2016/01/14/analysis-and-exploitation-of-a-linux-kernel-vulnerability-cve-2016-0728/" rel="nofollow" style="border: 0px; color: #1177b8; font-family: inherit; font-size: inherit; font-stretch: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; margin: 0px; outline: none; padding: 0px; text-decoration: none; vertical-align: baseline;" target="_blank">blog post</a> published today.<br style="content: ' '; display: block; margin: 6px 0px 0px; outline: 0px; padding: 0px;" /><i style="border: 0px; font-family: inherit; font-size: inherit; font-stretch: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">"With no auto update for the kernel, these versions could be vulnerable for a long time. Every Linux server needs to be patched as soon the patch is out."</i></blockquote>
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Usually, flaws in Linux kernel are patched as soon as they are found; therefore, Linux-based operating systems are considered to be more secure than others. However, zero-day vulnerability recently discovered in the Linux kernel made its way for almost 3 years.</div>
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The Cause of the Critical Linux Kernel Vulnerability</h3>
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The vulnerability is actually the result of a <b style="border: 0px; font-family: inherit; font-size: inherit; font-stretch: inherit; font-style: inherit; font-variant: inherit; line-height: inherit; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Reference Leak</b> in the keyrings facility built into various flavors of Linux. The keyrings facility is primarily a way to encrypt and store login data, encryption keys and certificates, and then make them available to applications.</div>
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However, a reference leak could be abused by attackers to ultimately execute arbitrary code in the Linux kernel.</div>
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So far, the researchers said, no exploits have been discovered in the wild that take advantage of this vulnerability.</div>
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Perception Point has provided a technical analysis of the vulnerability and how one can exploit it, including <a href="https://gist.github.com/PerceptionPointTeam/18b1e86d1c0f8531ff8f" rel="nofollow" style="border: 0px; color: #1177b8; font-family: inherit; font-size: inherit; font-stretch: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; margin: 0px; outline: none; padding: 0px; text-decoration: none; vertical-align: baseline;" target="_blank">proof-of-concept</a> (PoC) exploit code published on its Github page.</div>
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Patch Expected to Roll Out Soon</h3>
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The good news is that Perception Point has already reported the flaw to the Linux team, and patches are expected to roll out today to devices with automatic updates.</div>
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However, it may take a little longer on Android devices to receive the patch, given the fact that most updates aren’t pushed automatically by manufacturers and carriers.<br style="content: ' '; display: block; margin: 20px 0px 0px; outline: 0px; padding: 0px;" /><br style="content: ' '; display: block; margin: 20px 0px 0px; outline: 0px; padding: 0px;" /><h3 style="border: 0px; font-family: inherit; font-size: 1.4em; font-stretch: inherit; font-style: inherit; font-variant: inherit; line-height: 35px; margin: 0px; outline: 0px; padding: 0px; text-align: left !important; vertical-align: baseline;">
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Type following commands as per your Linux distro:</div>
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<li style="border: 0px; font-family: inherit; font-size: inherit; font-stretch: inherit; font-style: inherit; font-variant: inherit; font-weight: inherit; line-height: inherit; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;"><b style="border: 0px; font-family: inherit; font-size: inherit; font-stretch: inherit; font-style: inherit; font-variant: inherit; line-height: inherit; margin: 0px; outline: 0px; padding: 0px; vertical-align: baseline;">Debian or Ubuntu Linux:</b> sudo apt-get update && sudo apt-get upgrade</li>
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