Justin Ibarra
55 lines
1.8 KiB
TOML
55 lines
1.8 KiB
TOML
[metadata]
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creation_date = "2020/11/04"
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maturity = "production"
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updated_date = "2021/03/03"
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[rule]
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author = ["Elastic"]
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description = """
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Identifies unusual processes connecting to domains using known free SSL certificates. Adversaries may employ a known
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encryption algorithm to conceal command and control traffic.
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"""
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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 = "Connection to Commonly Abused Free SSL Certificate Providers"
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risk_score = 21
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rule_id = "e3cf38fa-d5b8-46cc-87f9-4a7513e4281d"
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severity = "low"
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tags = ["Elastic", "Host", "Windows", "Threat Detection", "Command and Control"]
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timestamp_override = "event.ingested"
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type = "eql"
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query = '''
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network where network.protocol == "dns" and
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/* Add new free SSL certificate provider domains here */
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dns.question.name : ("*letsencrypt.org", "*.sslforfree.com", "*.zerossl.com", "*.freessl.org") and
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/* Native Windows process paths that are unlikely to have network connections to domains secured using free SSL certificates */
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process.executable : ("C:\\Windows\\System32\\*.exe",
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"C:\\Windows\\System\\*.exe",
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"C:\\Windows\\SysWOW64\\*.exe",
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"C:\\Windows\\Microsoft.NET\\Framework*\\*.exe",
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"C:\\Windows\\explorer.exe",
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"C:\\Windows\\notepad.exe") and
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/* Insert noisy false positives here */
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not process.name : ("svchost.exe", "MicrosoftEdge*.exe", "msedge.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 = "T1573"
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name = "Encrypted Channel"
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reference = "https://attack.mitre.org/techniques/T1573/"
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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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