Samirbous
0c70d56dcd
* [Rule Tuning] Potential Command and Control via Internet Explorer * added FP note * update date * added *.office.com to exclusions
60 lines
1.9 KiB
TOML
60 lines
1.9 KiB
TOML
[metadata]
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creation_date = "2020/11/28"
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maturity = "production"
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updated_date = "2021/03/30"
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[rule]
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author = ["Elastic"]
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description = """
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Identifies instances of Internet Explorer (iexplore.exe) being started via the Component Object Model (COM) making
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unusual network connections. Adversaries could abuse Internet Explorer via COM to avoid suspicious processes making
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network connections and bypass host-based firewall restrictions.
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"""
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false_positives = ["Processes such as MS Office using IEproxy to render HTML content."]
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from = "now-9m"
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index = ["winlogbeat-*", "logs-endpoint.events.*", "logs-windows.*"]
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language = "eql"
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license = "Elastic License v2"
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name = "Potential Command and Control via Internet Explorer"
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risk_score = 47
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rule_id = "acd611f3-2b93-47b3-a0a3-7723bcc46f6d"
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severity = "medium"
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tags = ["Elastic", "Host", "Windows", "Threat Detection", "Command and Control"]
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type = "eql"
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query = '''
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sequence by host.id, user.id with maxspan = 5s
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[library where dll.name : "IEProxy.dll" and process.name : ("rundll32.exe", "regsvr32.exe")]
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[process where event.type == "start" and process.parent.name : "iexplore.exe" and process.parent.args : "-Embedding"]
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/* IE started via COM in normal conditions makes few connections, mainly to Microsoft and OCSP related domains, add FPs here */
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[network where network.protocol == "dns" and process.name : "iexplore.exe" and
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not dns.question.name :
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(
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"*.microsoft.com",
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"*.digicert.com",
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"*.msocsp.com",
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"*.windowsupdate.com",
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"*.bing.com",
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"*.identrust.com",
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"*.sharepoint.com",
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"*.office365.com",
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"*.office.com"
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)
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]
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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 = "T1071"
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name = "Application Layer Protocol"
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reference = "https://attack.mitre.org/techniques/T1071/"
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[rule.threat.tactic]
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id = "TA0011"
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name = "Command and Control"
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reference = "https://attack.mitre.org/tactics/TA0011/"
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