[New Rule] New Systemd Timer Created (#2601)

* [New Rule] New Systemd Timer Created * improve query runtime performance * added process.name entries for alert reduction * attempt to fix gh unit testing failure * added host.os.type==linux to fix unit test error * Added OSQuery to investigation guides * added additional process names * removed investigation guides to add in future PR * removed investigation guide tag * Changed rule to new_terms rule to reduce FPs * fixed query * formatting fix * Learnt another thing about KQL.. Formatting fix. * unit test fix * Update rules/linux/persistence_systemd_scheduled_timer_created.toml Co-authored-by: eric-forte-elastic <119343520+eric-forte-elastic@users.noreply.github.com> --------- Co-authored-by: Mika Ayenson <Mikaayenson@users.noreply.github.com> Co-authored-by: eric-forte-elastic <119343520+eric-forte-elastic@users.noreply.github.com>
2023-06-13 09:15:47 +02:00
parent 450e84ffa2
commit 644d2f5b26
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+[metadata]
+creation_date = "2023/02/24"
+integration = ["endpoint"]
+maturity = "production"
+min_stack_comments = "New fields added: required_fields, related_integrations, setup, New Term"
+min_stack_version = "8.6.0"
+updated_date = "2023/04/05"
+
+[rule]
+author = ["Elastic"]
+description = """
+Detects the creation of a systemd timer within any of the default systemd timer directories. Systemd timers can be used 
+by an attacker to gain persistence, by scheduling the execution of a command or script. Similarly to cron/at, systemd 
+timers can be set up to execute on boot time, or on a specific point in time, which allows attackers to regain access in 
+case the connection to the infected asset was lost. 
+"""
+from = "now-9m"
+index = ["logs-endpoint.events.*", "endgame-*"]
+language = "kuery"
+license = "Elastic License v2"
+name = "New Systemd Timer Created"
+references = [
+    "https://opensource.com/article/20/7/systemd-timers",
+    "https://pberba.github.io/security/2022/01/30/linux-threat-hunting-for-persistence-systemd-timers-cron/"
+]
+risk_score = 21
+rule_id = "7fb500fa-8e24-4bd1-9480-2a819352602c"
+severity = "low"
+tags = ["Elastic", "Host", "Linux", "Threat Detection", "Persistence", "Elastic Endgame"]
+timestamp_override = "event.ingested"
+type = "new_terms"
+
+query = '''
+host.os.type : "linux" and event.action : ("creation" or "file_create_event") and file.extension : "timer" and
+file.path : (/etc/systemd/system/* or /usr/local/lib/systemd/system/* or /lib/systemd/system/* or 
+/usr/lib/systemd/system/* or /home/*/.config/systemd/user/*) and not 
+process.executable : ("/usr/bin/dpkg" or "/usr/bin/dockerd" or "/bin/rpm")
+'''
+
+[[rule.threat]]
+framework = "MITRE ATT&CK"
+[[rule.threat.technique]]
+id = "T1053"
+name = "Scheduled Task/Job"
+reference = "https://attack.mitre.org/techniques/T1053/"
+[[rule.threat.technique.subtechnique]]
+id = "T1053.006"
+name = "Systemd Timers"
+reference = "https://attack.mitre.org/techniques/T1053/006/"
+
+
+
+[rule.threat.tactic]
+id = "TA0003"
+name = "Persistence"
+reference = "https://attack.mitre.org/tactics/TA0003/"
+
+
+[rule.new_terms]
+field = "new_terms_fields"
+value = ["file.path", "process.name"]
+[[rule.new_terms.history_window_start]]
+field = "history_window_start"
+value = "now-7d"