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libcurl wrong re-use of connections

                     libcurl wrong re-use of connections
                     ===================================
 
Project cURL Security Advisory, March 26th 2014
http://curl.haxx.se/docs/security.html
 
1. VULNERABILITY
 
  libcurl can in some circumstances re-use the wrong connection when asked to
  do transfers using other protocols than HTTP and FTP.
 
  libcurl features a pool of recent connections so that subsequent requests
  can re-use an existing connection to avoid overhead.
 
  When re-using a connection a range of criterion must first be met. Due to an
  error in the code, a transfer that was initiated by an application could
  wrongfully re-use an existing connection to the same server that was
  authenticated using different credentials. The existing logic basically only
  worked well enough for HTTP and FTP, while all other network protocols were
  silently, but erroneously, assumed to work like HTTP. Basically, protocols
  that use connection oriented authentication need a new connection when new
  credentials are used.
 
  Affected protocols include: SCP, SFTP, POP3(S), IMAP(S), SMTP(S) and
  LDAP(S).
 
  Applications can disable libcurl's re-use of connections and thus mitigate
  this problem, by using one of the following libcurl options to alter how
  connections are or aren't re-used: CURLOPT_FRESH_CONNECT,
  CURLOPT_MAXCONNECTS and CURLMOPT_MAX_HOST_CONNECTIONS (if using curl_multi
  API).
 
  (This problem is very similar to a problem previously reported to NTLM HTTP
  connections, named CVE-2014-0015)
 
  The Common Vulnerabilities and Exposures (CVE) project has assigned the name
  CVE-2014-0138 to this issue.
 
2. AFFECTED VERSIONS
 
  This flaw has existed ever since libcurl started to support these other
  protocols, although the code has been restructured a few times over the
  years so the mistake has altered shape.
 
  Affected versions: from libcurl 7.10.6 to and including 7.35.0
  Not affected versions: libcurl before 7.10.6 and >= 7.36.0
 
  libcurl is used by many applications, but not always advertised as such!
 
3. THE SOLUTION
 
  libcurl 7.36.0 makes sure that connections are re-used more strictly.
 
  A patch for this problem is available at:
 
    http://curl.haxx.se/libcurl-bad-reuse.patch
 
4. RECOMMENDATIONS
 
  We suggest you take one of the following actions immediately, in order of
  preference:
 
  A - Upgrade to curl and libcurl 7.36.0
 
  B - Apply the patch and rebuild libcurl
 
5. TIME LINE
 
  It was reported to the curl project on February 15th 2014. We contacted
  distros@openwall on March 16 2014.
 
  libcurl 7.36.0 was released on March 26th 2014, coordinated with the
  publication of this advisory.
 
6. CREDITS
 
  Bug reported and patch written by Steve Holme.
 
  Thanks a lot!