<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE glsa SYSTEM "http://www.gentoo.org/dtd/glsa.dtd">
<glsa id="201701-74">
  <title>libpng: Remote execution of arbitrary code</title>
  <synopsis>A null pointer dereference in libpng might allow remote attackers
    to execute arbitrary code.
  </synopsis>
  <product type="ebuild">libpng</product>
  <announced>2017-01-29</announced>
  <revised count="1">2017-01-29</revised>
  <bug>604082</bug>
  <access>remote</access>
  <affected>
    <package name="media-libs/libpng" auto="yes" arch="*">
      <unaffected range="ge">1.6.27</unaffected>
      <unaffected range="ge" slot="1.5">1.5.28</unaffected>
      <unaffected range="ge" slot="1.2">1.2.57</unaffected>
      <vulnerable range="lt">1.6.27</vulnerable>
    </package>
  </affected>
  <background>
    <p>libpng is a standard library used to process PNG (Portable Network
      Graphics) images. It is used by several programs, including web browsers
      and potentially server processes.
    </p>
  </background>
  <description>
    <p>A null pointer dereference was discovered in libpng in the
      png_push_save_buffer function.  In order to be vulnerable, an application
      has to load a text chunk into the PNG structure, then delete all text,
      then add another text chunk to the same PNG structure, which seems to be
      an unlikely sequence, but it is possible.
    </p>
  </description>
  <impact type="normal">
    <p>A remote attacker, by enticing a user to process a specially crafted PNG
      file, could execute arbitrary code with the privileges of the process.
    </p>
  </impact>
  <workaround>
    <p>There is no known workaround at this time.</p>
  </workaround>
  <resolution>
    <p>All libpng 1.6.x users should upgrade to the latest version:</p>
    
    <code>
      # emerge --sync
      # emerge --ask --oneshot --verbose "&gt;=media-libs/libpng-1.6.27"
    </code>
    
    <p>All libpng 1.5.x users should upgrade to the latest version:</p>
    
    <code>
      # emerge --sync
      # emerge --ask --oneshot --verbose "&gt;=media-libs/libpng-1.5.28:1.5"
    </code>
    
    <p>All libpng 1.2.x users should upgrade to the latest version:</p>
    
    <code>
      # emerge --sync
      # emerge --ask --oneshot --verbose "&gt;=media-libs/libpng-1.2.57:1.2"
    </code>
  </resolution>
  <references>
    <uri link="https://nvd.nist.gov/nvd.cfm?cvename=CVE-2016-10087">
      CVE-2016-10087
    </uri>
  </references>
  <metadata tag="requester" timestamp="2017-01-18T08:20:53Z">b-man</metadata>
  <metadata tag="submitter" timestamp="2017-01-29T17:07:28Z">b-man</metadata>
</glsa>
