"Nebula takes the participant through a variety of common (and less than common) weaknesses and vulnerabilities in Linux. Such as:
- SUID files
- Permissions
- Race conditions
- Shell meta-variables
- $PATH weaknesses
- Scripting language weaknesses
- Binary compilation failures
At the end of Nebula, the user will have a reasonably thorough understanding of local attacks against Linux systems, and a cursory look at some of the remote attacks that are possible."
I'm uploading the proofs and answers of each level as I progress. Please note that these are my own methods of finding and that others may have better ways to accomplish the task.