STRLCPY/SystemFunction032_Shellcode

Total 1 files

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rc4_encrypt.py

1	+	#!/usr/bin/env python3
2	+
3	+	from typing import Iterator
4	+	from base64 import b64encode
5	+
6	+
7	+	# Stolen from: https://gist.github.com/hsauers5/491f9dde975f1eaa97103427eda50071
8	+	def key_scheduling(key: bytes) -> list:
9	+	sched = [i for i in range(0, 256)]
10	+
11	+	i = 0
12	+	for j in range(0, 256):
13	+	i = (i + sched[j] + key[j % len(key)]) % 256
14	+	tmp = sched[j]
15	+	sched[j] = sched[i]
16	+	sched[i] = tmp
17	+
18	+	return sched
19	+
20	+
21	+	def stream_generation(sched: list[int]) -> Iterator[bytes]:
22	+	i, j = 0, 0
23	+	while True:
24	+	i = (1 + i) % 256
25	+	j = (sched[i] + j) % 256
26	+	tmp = sched[j]
27	+	sched[j] = sched[i]
28	+	sched[i] = tmp
29	+	yield sched[(sched[i] + sched[j]) % 256]
30	+
31	+
32	+	def encrypt(plaintext: bytes, key: bytes) -> bytes:
33	+	sched = key_scheduling(key)
34	+	key_stream = stream_generation(sched)
35	+
36	+	ciphertext = b''
37	+	for char in plaintext:
38	+	enc = char ^ next(key_stream)
39	+	ciphertext += bytes([enc])
40	+
41	+	return ciphertext
42	+
43	+
44	+	if __name__ == '__main__':
45	+	# msfvenom -p windows/x64/exec CMD=calc.exe -f raw -o calc.bin
46	+	with open('calc.bin', 'rb') as f:
47	+	result = encrypt(plaintext=f.read(), key=b'aaaaaaaaaaaaaaaa')
48	+
49	+	print(b64encode(result).decode())