Ubuntu Linux and the Heartbleed OpenSSL vulnerability.

If you're in the mad scramble to patch the Heartbleed vulnerability in OpenSSL on your Ubuntu servers but you need to see some documentation, look in your /usr/share/doc/openssl/changelog.Debian.gz file. If you see the following at the very top of the file, you're patched:

 
openssl (1.0.1-4ubuntu5.12) precise-security; urgency=medium  
  * SECURITY UPDATE: side-channel attack on Montgomery ladder implementation 
    - debian/patches/CVE-2014-0076.patch: add and use constant time swap in 
      crypto/bn/bn.h, crypto/bn/bn_lib.c, crypto/ec/ec2_mult.c, 
      util/libeay.num. 
    - CVE-2014-0076 
  * SECURITY UPDATE: memory disclosure in TLS heartbeat extension 
    - debian/patches/CVE-2014-0160.patch: use correct lengths in 
      ssl/d1_both.c, ssl/t1_lib.c. 
    - CVE-2014-0160  
 -- Marc Deslauriers   Mon, 07 Apr 2014 15:45:14 -0400 

If you don't, run sudo apt-get update followed by sudo apt-get upgrade -y and then reboot the machine to make sure everything linked against OpenSSL gets restarted and uses the new code. Better safe than sorry.