<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE glsa SYSTEM "http://www.gentoo.org/dtd/glsa.dtd">
<glsa id="200405-06">
  <title>libpng denial of service vulnerability</title>
  <synopsis>
    A bug in the libpng library can be abused to crash programs making use of
    that library to decode PNG images.
  </synopsis>
  <product type="ebuild">libpng</product>
  <announced>2004-05-14</announced>
  <revised count="01">2004-05-14</revised>
  <bug>49887</bug>
  <access>remote </access>
  <affected>
    <package name="media-libs/libpng" auto="yes" arch="*">
      <unaffected range="ge">1.2.5-r5</unaffected>
      <vulnerable range="le">1.2.5-r4</vulnerable>
    </package>
  </affected>
  <background>
    <p>
    libpng is a standard library used to process PNG (Portable Network
    Graphics) images.
    </p>
  </background>
  <description>
    <p>
    libpng provides two functions (png_chunk_error and png_chunk_warning) for
    default error and warning messages handling. These functions do not perform
    proper bounds checking on the provided message, which is limited to 64
    bytes. Programs linked against this library may crash when handling a
    malicious PNG image.
    </p>
  </description>
  <impact type="normal">
    <p>
    This vulnerability could be used to crash various programs using the libpng
    library, potentially resulting in a denial of service attack on vulnerable
    daemon processes.
    </p>
  </impact>
  <workaround>
    <p>
    There is no known workaround at this time. All users are advised to upgrade
    to the latest available version of libpng.
    </p>
  </workaround>
  <resolution>
    <p>
    All users of libpng should upgrade to the latest stable version:
    </p>
    <code>
    # emerge sync

    # emerge -pv "&gt;=media-libs/libpng-1.2.5-r5"
    # emerge "&gt;=media-libs/libpng-1.2.5-r5"</code>
    <p>
    You should also run revdep-rebuild to rebuild any packages that depend on
    older versions of libpng :
    </p>
    <code>
    # revdep-rebuild</code>
  </resolution>
  <references>
    <uri link="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2004-0421">CAN-2004-0421</uri>
  </references>
  <metadata tag="submitter">
    koon
  </metadata>
</glsa>
