sycat

sycat is netcat implementation in python3.

Reason why create this script ?

• tired of spawning pty shell and configure the terminal size every time get reverse shell connection while playing boot2root ctf.
• learn more about socket implementation.

Update V0.4

due to compiling .exe binary now the script require go to be installed and upx for compressing the exe payload.

some update:

• now support listen or connect with ssl (--ssl).
• change the encode options to (-en) instead of (-e).
• execute command to execute for listen or connect is now supported.
• options -host and -p to specify ip and port is now changed to positional argument, where the default value of ip is 0.0.0.0

Feature

Sycat currently support spawning pty shell and configure the terminal size automatically and also support:

• read stdin as input.
• support raw tty mode (stty raw -echo).
• using built in python module (no need to install any module).
• support generating payload only in bash,nc, and exe.
• auto spawn pty shell and configure the terminal size automatically with options (-tty)
• bypass amsi is supported with options (-amsi)
• ssl is now supported !
• execute command to execute for listen or connect.

Known Issue

• options -e to execute command for listen or connect currently not compatible with --ssl.

Install

Clone:

git clone https://github.com/zulfi0/sycat

Run the script:

chmod +x scat.py && ./scat.py --help

Example

listen incoming connection:

./scat.py -vl 1337

auto spawning pty shell when received reverse shell connection:

./scat.py -vl 1337 -tty

auto spawning pty shell when connected to bind shell connection:

./scat.py -v 127.0.0.1 1337 -tty

to listen with SSL first generate the key and cert file:

openssl req -x509 -newkey rsa:4096 -keyout server-key.pem -out server-cert.pem -days 365 -nodes

listen with ssl key and cert file:

sycat -vl 1337 --ssl --ssl-key server-key.pem --ssl-cert server-cert.pem

or connect with ssl:

sycat -v 127.0.0.1 1337 --ssl --ssl-key server-key.pem --ssl-cert server-cert.pem

To do

• add powershell script payload and its obfuscate

If you have any suggestion or request feature or find any errors please create an issue.