I published the following diary on isc.sans.edu: “The UPX Packer Will Never Die!“:
Today, many malware samples that you can find in the wild are “packed”. The process of packing an executable file is not new and does not mean that it is de-facto malicious. Many developers decide to pack their software to protect the code. But why malware are often packed? Because packing slows down the malware analyst job and defeats many static analysis tools. The advantages of packed malware (from an attacker’s point of view) are (amongst others)… [Read more]