(http://curl.haxx.se/bug/view.cgi?id=2829955) mentioning the recent SSL cert
  verification flaw found and exploited by Moxie Marlinspike. The presentation
  he did at Black Hat is available here:
  https://www.blackhat.com/html/bh-usa-09/bh-usa-09-archives.html#Marlinspike

  Apparently at least one CA allowed a subjectAltName or CN that contain a
  zero byte, and thus clients that assumed they would never have zero bytes
  were exploited to OK a certificate that didn't actually match the site. Like
  if the name in the cert was "example.com\0theatualsite.com", libcurl would
  happily verify that cert for example.com.

  libcurl now better use the length of the extracted name, not assuming it is
  zero terminated.

  only in some OpenSSL installs - like on Windows) isn't thread-safe and we
  agreed that moving it to the global_init() function is a decent way to deal
  with this situation.

  CURLOPT_NOPROXY to "*", or to a host that should not use a proxy, I actually
  could still end up using a proxy if a proxy environment variable was set.

  CURLOPT_PREQUOTE) now accept a preceeding asterisk before the command to
  send when using FTP, as a sign that libcurl shall simply ignore the response
  from the server instead of treating it as an error. Not treating a 400+ FTP
  response code as an error means that failed commands will not abort the
  chain of commands, nor will they cause the connection to get disconnected.

  out that OpenSSL-powered libcurl didn't support the SHA-2 digest algorithm,
  and provided the solution too: to use OpenSSL_add_all_algorithms() instead
  of the older SSLeay_* alternative. OpenSSL_add_all_algorithms was added in
  OpenSSL 0.9.5

  They introduce known_host support for SSH keys to libcurl. See docs for
  details.

  (https://bugzilla.novell.com/523919). When looking at the code, I found
  that also the ptr pointer can leak.

  (http://curl.haxx.se/bug/view.cgi?id=2813123) and an a patch that fixes the
  problem:

  Url A is accessed using auth. Url A redirects to Url B (on a different
  server0. Url B reuses a persistent connection. Url B has auth, even though
  it's on a different server.

  Note: if Url B does not reuse a persistent connection, auth is not sent.

  range if given colon-separated after the host name/address part. Like
  "192.168.0.1:2000-10000"

  (no newline translations). Use -B/--use-ascii if you rather get the ascii
  approach.

  provided in the url, add it there (squid needs this).

  This allows curl(1) to be used as a client-side tunnel for arbitrary stream
  protocols by abusing chunked transfer encoding in both the HTTP request and
  HTTP response.  This requires server support for sending a response while a
  request is still being read, of course.

  If attempting to read from stdin returns EAGAIN, then we pause our sender.
  This leaves curl to attempt to read from the socket while reading from stdin
  (and thus sending) is paused.

  contributed a range of patches to fix them.

  issue with client certs that caused issues like segfaults.
  http://curl.haxx.se/mail/lib-2009-05/0316.html

  to detect gnutls build options with pkg-config only and not libgnutls-config
  anymore since GnuTLS has stopped distributing that tool. If an explicit path
  is given to configure, we will instead guess on how to link and use that
  lib. I did not use the patch from the bug report.

- Added some cmake docs and fixed socklen_t in the build.

  broken since 7.19.0

  is almost always a VERY BAD IDEA. Yet there are still apps out there doing
  this, and now recently it triggered a bug/side-effect in libcurl as when
  libcurl sends a POST or PUT with NTLM, it sends an empty post first when it
  knows it will just get a 401/407 back. If the app then replaced the
  Content-Length header, it caused the server to wait for input that libcurl
  wouldn't send. Aaron Oneal reported this problem in bug report #2799008
  http://curl.haxx.se/bug/view.cgi?id=2799008) and helped us verify the fix.

  without pkg-config.

  PK11_CreateGenericObject() function.

  the auth credentials back in 7.19.0 and earlier while now you have to set ""
  to get the same effect. His patch brings back the ability to use NULL.

  for a failure properly.

  fine with Nokia 5th edition 1.0 SDK for Symbian.

  out that the cookie parser would leak memory when it parses cookies that are
  received with domain, path etc set multiple times in the same header. While
  such a cookie is questionable, they occur in the wild and libcurl no longer
  leaks memory for them. I added such a header to test case 8.

  https://bugzilla.redhat.com/show_bug.cgi?id=427966 which was libcurl closing
  a bad file descriptor when closing down the FTP data connection.  Caolan
  McNamara seems to be the original author of it.

  no_proxy which made it not skip the proxy if the URL entered contained a
  user name. I added test case 1101 to verify.

  of streams that had some parts (legitimately) missing. We now provide and use
  a proper cleanup function for the content encoding submodule.
  http://curl.haxx.se/mail/lib-2009-05/0092.html

  at https://bugzilla.redhat.com/show_bug.cgi?id=453612#c12

  If an incorrect password is given while loading a private key, libcurl ends
  up in an infinite loop consuming memory. The bug is critical.

  as reported by Ebenezer Ikonne (on curl-users) and Laurent Rabret (on
  curl-library). The transfer was mistakenly marked to get more data to send
  but since it didn't actually have that, it just hung there...

to work so I'll let it remain and here's the comment about it! From Lenaic's
mail posted to curl-library Date: Fri, 1 May 2009 22:46:14 +0200.

  (http://curl.haxx.se/bug/view.cgi?id=2784055) identifying a problem to
  connect to SOCKS proxies when using the multi interface. It turned out to
  almost not work at all previously. We need to wait for the TCP connect to
  be properly verified before doing the SOCKS magic.

  There's still a flaw in the FTP code for this.

  reported in the Debian package.