sigma-rules/rules/linux/persistence_credential_access_modify_ssh_binaries.toml

[metadata]
creation_date = "2020/12/21"
integration = ["endpoint"]
maturity = "production"
min_stack_comments = "New fields added: required_fields, related_integrations, setup"
min_stack_version = "8.3.0"
updated_date = "2023/02/22"

[rule]
author = ["Elastic"]
description = """
Adversaries may modify SSH related binaries for persistence or credential access by patching sensitive functions to
enable unauthorized access or by logging SSH credentials for exfiltration.
"""
false_positives = [
    "Trusted OpenSSH executable updates. It's recommended to verify the integrity of OpenSSH binary changes.",
]
from = "now-9m"
index = ["auditbeat-*", "logs-endpoint.events.*", "endgame-*"]
language = "kuery"
license = "Elastic License v2"
name = "Modification of OpenSSH Binaries"
references = ["https://blog.angelalonso.es/2016/09/anatomy-of-real-linux-intrusion-part-ii.html"]
risk_score = 47
rule_id = "0415f22a-2336-45fa-ba07-618a5942e22c"
severity = "medium"
tags = ["Elastic", "Host", "Linux", "Threat Detection", "Credential Access", "Persistence", "Lateral Movement", "Elastic Endgame"]
timestamp_override = "event.ingested"
type = "query"

query = '''
event.category:file and host.os.type:linux and event.type:change and
 process.name:* and
 (file.path:(/usr/sbin/sshd or /usr/bin/ssh or /usr/bin/sftp or /usr/bin/scp) or file.name:libkeyutils.so) and
 not process.name:("dpkg" or "yum" or "dnf" or "dnf-automatic")
'''


[[rule.threat]]
framework = "MITRE ATT&CK"
[[rule.threat.technique]]
id = "T1543"
name = "Create or Modify System Process"
reference = "https://attack.mitre.org/techniques/T1543/"


[rule.threat.tactic]
id = "TA0003"
name = "Persistence"
reference = "https://attack.mitre.org/tactics/TA0003/"

[[rule.threat]]
framework = "MITRE ATT&CK"
[[rule.threat.technique]]
id = "T1556"
name = "Modify Authentication Process"
reference = "https://attack.mitre.org/techniques/T1556/"


[rule.threat.tactic]
id = "TA0006"
name = "Credential Access"
reference = "https://attack.mitre.org/tactics/TA0006/"




[[rule.threat]]
framework = "MITRE ATT&CK"
[[rule.threat.technique]]
id = "T1563"
name = "Remote Service Session Hijacking"
reference = "https://attack.mitre.org/techniques/T1563/"
[[rule.threat.technique.subtechnique]]
id = "T1563.001"
name = "SSH Hijacking"
reference = "https://attack.mitre.org/techniques/T1563/001/"

[[rule.threat.technique]]
id = "T1021"
name = "Remote Services"
reference = "https://attack.mitre.org/techniques/T1021/"
[[rule.threat.technique.subtechnique]]
id = "T1021.004"
name = "SSH"
reference = "https://attack.mitre.org/techniques/T1021/004/"

[rule.threat.tactic]
id = "TA0008"
name = "Lateral Movement"
reference = "https://attack.mitre.org/tactics/TA0008/"