privilege escalation - world-writable directories and files

Often, privilege escalation exploits and other such malware requires write access to the filesystem in order to store and run the payload.

On Linux and Unix-like systems, several world-writable directories may be present:

• /tmp
• /var/tmp
• /dev/shm

…

If a user of the system has set permissions to be readable, writable and executable by anyone on the system using something like `chmod 777 file`, an attacker may over-write the contents of one of these files with their payload and execute it.

---