66 lines
2.0 KiB
Python
66 lines
2.0 KiB
Python
# Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
|
|
# or more contributor license agreements. Licensed under the Elastic License
|
|
# 2.0; you may not use this file except in compliance with the Elastic License
|
|
# 2.0.
|
|
|
|
# Name: Encrypting files with 7zip
|
|
# RTA: sevenzip_encrypted.py
|
|
# ATT&CK: T1022
|
|
# Description: Uses "bin\.exe" to perform encryption of archives and archive headers.
|
|
|
|
import base64
|
|
import sys
|
|
from pathlib import Path
|
|
|
|
from . import RtaMetadata, common
|
|
|
|
metadata = RtaMetadata(
|
|
uuid="6cd35061-278b-45e7-a9cb-86b48bc47884",
|
|
platforms=["windows"],
|
|
endpoint=[],
|
|
siem=[{"rule_id": "45d273fb-1dca-457d-9855-bcb302180c21", "rule_name": "Encrypting Files with WinRar or 7z"}],
|
|
techniques=["T1560"],
|
|
)
|
|
|
|
|
|
SEVENZIP = common.get_path("bin", "7za.exe")
|
|
|
|
|
|
def create_exfil(path=Path("secret_stuff.txt").resolve()):
|
|
common.log("Writing dummy exfil to %s" % path)
|
|
with open(path, "wb") as f:
|
|
f.write(base64.b64encode(b"This is really secret stuff\n" * 100))
|
|
return path
|
|
|
|
|
|
@common.requires_os(*metadata.platforms)
|
|
@common.dependencies(SEVENZIP)
|
|
def main(password="s0l33t"):
|
|
# create 7z.exe with not-7zip name, and exfil
|
|
svnz2 = Path("a.exe").resolve()
|
|
common.copy_file(SEVENZIP, svnz2)
|
|
exfil = create_exfil()
|
|
|
|
exts = ["7z", "zip", "gzip", "tar", "bz2", "bzip2", "xz"]
|
|
out_jpg = Path("out.jpg").resolve()
|
|
|
|
for ext in exts:
|
|
# Write archive for each type
|
|
out_file = Path("out." + ext).resolve()
|
|
common.execute([svnz2, "a", out_file, "-p" + password, exfil], mute=True)
|
|
common.remove_file(out_file)
|
|
|
|
# Write archive for each type with -t flag
|
|
if ext == "bz2":
|
|
continue
|
|
|
|
common.execute([svnz2, "a", out_jpg, "-p" + password, "-t" + ext, exfil], mute=True)
|
|
common.remove_file(out_jpg)
|
|
|
|
common.execute([SEVENZIP, "a", out_jpg, "-p" + password, exfil], mute=True)
|
|
common.remove_files(exfil, svnz2, out_jpg)
|
|
|
|
|
|
if __name__ == "__main__":
|
|
exit(main(*sys.argv[1:]))
|