defense_evasion_env_binary.toml

[metadata]
creation_date = "2022/02/24"
maturity = "production"
updated_date = "2022/03/04"

[rule]
author = ["Elastic"]
description = """
Identifies Linux binary env abuse to break out from restricted environments by spawning an interactive system shell.This
activity is not standard use with this binary for a user or system administrator. It indicates a potentially malicious
actor attempting to improve the capabilities or stability of their access
"""
from = "now-9m"
index = ["logs-endpoint.events.*"]
language = "eql"
license = "Elastic License v2"
name = "Linux Restricted Shell Breakout via env Shell Evasion"
references = ["https://gtfobins.github.io/gtfobins/env/"]
risk_score = 47
rule_id = "72d33577-f155-457d-aad3-379f9b750c97"
severity = "medium"
tags = ["Elastic", "Host", "Linux", "Threat Detection", "Defense Evasion", "GTFOBins"]
timestamp_override = "event.ingested"
type = "eql"

query = '''
process where event.type == "start" and process.name : "env" and process.args_count == 2 and process.args : ("/bin/sh", "/bin/bash", "sh", "bash")
'''


[[rule.threat]]
framework = "MITRE ATT&CK"
[[rule.threat.technique]]
id = "T1548"
name = "Abuse Elevation Control Mechanism"
reference = "https://attack.mitre.org/techniques/T1548/"
[[rule.threat.technique.subtechnique]]
id = "T1548.004"
name = "Elevated Execution with Prompt"
reference = "https://attack.mitre.org/techniques/T1548/004/"



[rule.threat.tactic]
id = "TA0005"
name = "Defense Evasion"
reference = "https://attack.mitre.org/tactics/TA0005/"