Recently, we came across a malware sample that has been traversing the Internet disguised as an image of a woman. The malware sample uses several layers of obfuscation to hide its payload, including the use of steganography.
more here.........http://blogs.cisco.com/security/talos/reversing-multilayer-net-malware
more here.........http://blogs.cisco.com/security/talos/reversing-multilayer-net-malware