<?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 ">=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>