There are a couple of useful tools that are already built into the operating system we are working on. These come in handy when third party tools are not available:

• strings: This is a Linux command used to list the strings found in a given file.
• md5sum: This is a Linux command used to calculate the MD5 hash of a given file.
• file: This is a command line in Linux used to identify files. It uses the libmagic library.