Justin Ibarra
6bdfddac8e
* Expand timestamp_override tests * removed timestamp_override from eql sequence rules * add config entry for eql rules with beats index and t_o * add timestamp_override to missing fields
58 lines
2.0 KiB
TOML
58 lines
2.0 KiB
TOML
[metadata]
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creation_date = "2021/03/04"
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maturity = "production"
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updated_date = "2022/03/31"
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[rule]
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author = ["Elastic", "Austin Songer"]
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description = """
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Identifies suspicious processes being spawned by the Microsoft Exchange Server Unified Messaging (UM) service. This
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activity has been observed exploiting CVE-2021-26857.
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"""
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false_positives = [
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"""
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Legitimate processes may be spawned from the Microsoft Exchange Server Unified Messaging (UM) service. If known
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processes are causing false positives, they can be exempted from the rule.
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""",
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]
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from = "now-9m"
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index = ["logs-endpoint.events.*", "winlogbeat-*", "logs-windows.*"]
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language = "eql"
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license = "Elastic License v2"
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name = "Microsoft Exchange Server UM Spawning Suspicious Processes"
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note = """## Config
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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.
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"""
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references = [
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"https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers",
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"https://www.volexity.com/blog/2021/03/02/active-exploitation-of-microsoft-exchange-zero-day-vulnerabilities",
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]
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risk_score = 47
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rule_id = "483c4daf-b0c6-49e0-adf3-0bfa93231d6b"
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severity = "medium"
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tags = ["Elastic", "Host", "Windows", "Threat Detection", "Initial Access"]
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timestamp_override = "event.ingested"
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type = "eql"
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query = '''
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process where event.type == "start" and
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process.parent.name : ("UMService.exe", "UMWorkerProcess.exe") and
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not process.name : ("werfault.exe", "wermgr.exe")
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'''
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[[rule.threat]]
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framework = "MITRE ATT&CK"
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[[rule.threat.technique]]
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id = "T1190"
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name = "Exploit Public-Facing Application"
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reference = "https://attack.mitre.org/techniques/T1190/"
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[rule.threat.tactic]
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id = "TA0001"
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name = "Initial Access"
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reference = "https://attack.mitre.org/tactics/TA0001/"
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