Justin Ibarra
46d5e37b76
* min_stack all rules to 8.3 * bump date Co-authored-by: Mika Ayenson <mika.ayenson@elastic.co>
94 lines
3.0 KiB
TOML
94 lines
3.0 KiB
TOML
[metadata]
|
|
creation_date = "2020/12/21"
|
|
maturity = "production"
|
|
min_stack_comments = "New fields added: required_fields, related_integrations, setup"
|
|
min_stack_version = "8.3.0"
|
|
updated_date = "2022/08/24"
|
|
|
|
[rule]
|
|
author = ["Elastic"]
|
|
description = """
|
|
Identifies a Secure Shell (SSH) client or server process creating or writing to a known SSH backdoor log file.
|
|
Adversaries may modify SSH related binaries for persistence or credential access via patching sensitive functions to
|
|
enable unauthorized access or to log SSH credentials for exfiltration.
|
|
"""
|
|
false_positives = ["Updates to approved and trusted SSH executables can trigger this rule."]
|
|
from = "now-9m"
|
|
index = ["auditbeat-*", "logs-endpoint.events.*"]
|
|
language = "eql"
|
|
license = "Elastic License v2"
|
|
name = "Potential OpenSSH Backdoor Logging Activity"
|
|
note = """## Setup
|
|
|
|
If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2, events will not define `event.ingested` and default fallback for EQL rules was not added until 8.2, so you will need to add a custom pipeline to populate `event.ingested` to @timestamp for this rule to work.
|
|
"""
|
|
references = [
|
|
"https://github.com/eset/malware-ioc/tree/master/sshdoor",
|
|
"https://www.welivesecurity.com/wp-content/uploads/2021/01/ESET_Kobalos.pdf",
|
|
]
|
|
risk_score = 73
|
|
rule_id = "f28e2be4-6eca-4349-bdd9-381573730c22"
|
|
severity = "high"
|
|
tags = ["Elastic", "Host", "Linux", "Threat Detection", "Persistence", "Credential Access"]
|
|
timestamp_override = "event.ingested"
|
|
type = "eql"
|
|
|
|
query = '''
|
|
file where event.type == "change" and process.executable : ("/usr/sbin/sshd", "/usr/bin/ssh") and
|
|
(
|
|
(file.name : (".*", "~*", "*~") and not file.name : (".cache", ".viminfo", ".bash_history")) or
|
|
file.extension : ("in", "out", "ini", "h", "gz", "so", "sock", "sync", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9") or
|
|
file.path :
|
|
(
|
|
"/private/etc/*--",
|
|
"/usr/share/*",
|
|
"/usr/include/*",
|
|
"/usr/local/include/*",
|
|
"/private/tmp/*",
|
|
"/private/var/tmp/*",
|
|
"/usr/tmp/*",
|
|
"/usr/share/man/*",
|
|
"/usr/local/share/*",
|
|
"/usr/lib/*.so.*",
|
|
"/private/etc/ssh/.sshd_auth",
|
|
"/usr/bin/ssd",
|
|
"/private/var/opt/power",
|
|
"/private/etc/ssh/ssh_known_hosts",
|
|
"/private/var/html/lol",
|
|
"/private/var/log/utmp",
|
|
"/private/var/lib",
|
|
"/var/run/sshd/sshd.pid",
|
|
"/var/run/nscd/ns.pid",
|
|
"/var/run/udev/ud.pid",
|
|
"/var/run/udevd.pid"
|
|
)
|
|
)
|
|
'''
|
|
|
|
|
|
[[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 = "T1554"
|
|
name = "Compromise Client Software Binary"
|
|
reference = "https://attack.mitre.org/techniques/T1554/"
|
|
|
|
|
|
[rule.threat.tactic]
|
|
id = "TA0003"
|
|
name = "Persistence"
|
|
reference = "https://attack.mitre.org/tactics/TA0003/"
|
|
|