metadata/glsa/glsa-200312-07.xml

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE glsa SYSTEM "http://www.gentoo.org/dtd/glsa.dtd">

<glsa id="200312-07">
  <title>Two buffer overflows in lftp</title>
  <synopsis>
    Two buffer overflow problems are found in lftp that, in case the user visits
    a malicious ftp server, could lead to malicious code being executed.
  </synopsis>
  <product type="ebuild">lftp</product>
  <announced>December 13, 2003</announced>
  <revised>200312-07: 2</revised>
  <bug>35866</bug>
  <access>remote</access>
  <affected>
    <package name="net-ftp/lftp" auto="yes" arch="*">
      <vulnerable range="lt">2.6.10</vulnerable>
      <unaffected range="ge">2.6.10</unaffected>
    </package>
  </affected>
  <background>
    <p>
    lftp is a multithreaded command-line based FTP client. It allows you to
    execute multiple commands simultaneously or in the background. If features
    mirroring capabilities, resuming downloads, etc.
    </p>
  </background>
  <description>
    <p>
    Two buffer overflows exist in lftp. Both can occur when the user connects to
    a malicious web server using the HTTP or HTTPS protocol and issues lftp's
    "ls" or "rels" commands.
    </p>
    <p>
    Ulf Harnhammar explains:
    </p>
    <p>
    Technically, the problem lies in the file src/HttpDir.cc and the
    functions try_netscape_proxy() and try_squid_eplf(), which both
    have sscanf() calls that take data of an arbitrary length and
    store it in a char array with 32 elements. (Back in version 2.3.0,
    the problematic code was located in some other function, but the
    problem existed back then too.) Depending on the HTML document in the 
    specially prepared directory, buffers will be overflown in either one 
    function or the other.
    </p>
  </description>
  <impact type="low">
    <p>
    When a user issues "ls" or "rels" on a malicious server, the tftp
    application can be tricked into running arbitrary code on the user his
    machine.
    </p>
  </impact>
  <workaround>
    <p>
    There is no workaround available.
    </p>
  </workaround>
  <resolution>
    <p>
    All Gentoo users who have net-ftp/lftp installed should update to use
    version 2.6.0 or higher using these commands:
    </p>
    <code>
    # emerge sync
    # emerge -pv '>=net-ftp/lftp-2.6.10'
    # emerge '>=net-ftp/lftp-2.6.10'
    # emerge clean</code>
  </resolution>
  <references>
    <uri link="http://www.securityfocus.com/archive/1/347587/2003-12-13/2003-12-19/0">Initial report by Ulf Harnhammar</uri>
  </references>
</glsa>