LSMS/scripts/search_memfd_create.py

74 lines
1.7 KiB
Python
Executable File

#!/usr/bin/env python3
# written by sqall
# twitter: https://twitter.com/sqall01
# blog: https://h4des.org
# github: https://github.com/sqall01
#
# Licensed under the MIT License.
"""
Short summary:
Malware uses calls such as memfd_create() to create an anonymous file in RAM that can be run.
Requirements:
None
Reference:
https://www.sandflysecurity.com/blog/detecting-linux-memfd_create-fileless-malware-with-command-line-forensics/
"""
import os
import sys
from lib.util import output_finding
# Read configuration.
try:
from config.config import ALERTR_FIFO, FROM_ADDR, TO_ADDR
from config.search_memfd_create import ACTIVATED
except:
ALERTR_FIFO = None
FROM_ADDR = None
TO_ADDR = None
ACTIVATED = True
def search_deleted_memfd_files():
# Decide where to output results.
print_output = False
if ALERTR_FIFO is None and FROM_ADDR is None and TO_ADDR is None:
print_output = True
if not ACTIVATED:
if print_output:
print("Module deactivated.")
return
# Get all suspicious ELF files.
fd = os.popen("ls -laR /proc/*/exe 2> /dev/null | grep memfd:.*\\(deleted\\)")
suspicious_exe_raw = fd.read().strip()
fd.close()
suspicious_exes = []
if suspicious_exe_raw.strip():
suspicious_exes.extend(suspicious_exe_raw.strip().split("\n"))
if suspicious_exes:
message = "Deleted memfd file(s) found:\n\n"
message += "\n".join(suspicious_exes)
output_finding(__file__, message)
if __name__ == '__main__':
is_init_run = False
if len(sys.argv) == 2:
if sys.argv[1] == "--init":
is_init_run = True
# Script does not need to establish a state.
if not is_init_run:
search_deleted_memfd_files()