<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE glsa SYSTEM "http://www.gentoo.org/dtd/glsa.dtd">
<glsa id="201507-15">
  <title>OpenSSL: Alternate chains certificate forgery</title>
  <synopsis>Certain checks on untrusted certificates can be bypassed.</synopsis>
  <product type="ebuild">openssl</product>
  <announced>July 10, 2015</announced>
  <revised>February 26, 2016: 3</revised>
  <bug>554172</bug>
  <access>remote</access>
  <affected>
    <package name="dev-libs/openssl" auto="yes" arch="*">
      <unaffected range="ge">1.0.1p</unaffected>
      <unaffected range="rge">0.9.8z_p6</unaffected>
      <unaffected range="rge">0.9.8z_p7</unaffected>
      <unaffected range="rge">0.9.8z_p8</unaffected>
      <unaffected range="rge">0.9.8z_p9</unaffected>
      <unaffected range="rge">0.9.8z_p10</unaffected>
      <unaffected range="rge">0.9.8z_p11</unaffected>
      <unaffected range="rge">0.9.8z_p12</unaffected>
      <unaffected range="rge">0.9.8z_p13</unaffected>
      <unaffected range="rge">0.9.8z_p14</unaffected>
      <unaffected range="rge">0.9.8z_p15</unaffected>
      <vulnerable range="lt">1.0.1p</vulnerable>
    </package>
  </affected>
  <background>
    <p>OpenSSL is an Open Source toolkit implementing the Secure Sockets Layer
      (SSL v2/v3) and Transport Layer Security (TLS v1) as well as a general
      purpose cryptography library.
    </p>
  </background>
  <description>
    <p>During certificate verification, OpenSSL attempts to find an alternative
      certificate chain if the first attempt to build such a chain fails.
    </p>
  </description>
  <impact type="normal">
    <p>A remote attacker could cause certain checks on untrusted
      certificates to be bypassed, such as the CA flag, enabling them to use a
      valid leaf certificate to act as a CA and “issue” an invalid
      certificate.
    </p>
  </impact>
  <workaround>
    <p>There is no known workaround at this time.</p>
  </workaround>
  <resolution>
    <p>All OpenSSL users should upgrade to the latest version:</p>
    
    <code>
      # emerge --sync
      # emerge --ask --oneshot --verbose "&gt;=dev-libs/openssl-1.0.1p"
    </code>
    
  </resolution>
  <references>
    <uri link="http://nvd.nist.gov/nvd.cfm?cvename=CVE-2015-1793">CVE-2015-1793</uri>
  </references>
  <metadata tag="requester" timestamp="Wed, 08 Jul 2015 09:20:30 +0000">
    keytoaster
  </metadata>
  <metadata tag="submitter" timestamp="Fri, 26 Feb 2016 14:46:50 +0000">
    keytoaster
  </metadata>
</glsa>