[New/Tuning] Windows Rules to detect top threats/TTPs 24/25

rules/windows/command_and_control_dns_susp_tld.toml

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+[metadata]
+creation_date = "2025/08/20"
+integration = ["endpoint", "windows", "sentinel_one_cloud_funnel", "crowdstrike"]
+maturity = "production"
+updated_date = "2025/08/20"
+
+[rule]
+author = ["Elastic"]
+description = """
+Identifies DNS queries to commonly abused Top Level Domains by common LOLBINs or executable running from world writable
+directories or unsigned binaries. This behavior matches on common malware C2 abusing less formal domain names.
+"""
+from = "now-9m"
+index = [
+    "endgame-*",
+    "logs-endpoint.events.network-*",
+    "logs-sentinel_one_cloud_funnel.*",
+    "logs-crowdstrike.fdr*",
+    "logs-windows.forwarded*",
+    "logs-windows.sysmon_operational-*",
+    "winlogbeat-*"
+]
+language = "eql"
+license = "Elastic License v2"
+name = "Network Activity to a Suspicious Top Level Domain"
+note = """## Triage and analysis
+
+### Investigating Network Activity to a Suspicious Top Level Domain
+
+#### Possible investigation steps
+
+- Investigate the process execution chain (parent process tree) for unknown processes or malicious scripts.
+- Review if the domain reputation and the frequency of network activities as well as any download/upload activity.
+- Verify if the executed process is persistent on the host like common mechanisms Startup folder, task or Run key.
+- Investigate other alerts associated with the user/host during the past 48 hours.
+- Extract this communication's indicators of compromise (IoCs) and use traffic logs to search for other potentially compromised hosts.
+
+### False positive analysis
+
+- Trusted domain from an expected process running in the environment.
+
+### Response and remediation
+
+- Initiate the incident response process based on the outcome of the triage.
+- Isolate the involved host to prevent further post-compromise behavior.
+- Immediately block the identified indicators of compromise (IoCs).
+- Implement any temporary network rules, procedures, and segmentation required to contain the attack.
+- Investigate credential exposure on systems compromised or used by the attacker to ensure all compromised accounts are identified. Reset passwords for these accounts and other potentially compromised credentials, such as email, business systems, and web services.
+- Update firewall rules to be more restrictive.
+- Reimage the host operating system or restore the compromised files to clean versions.
+- Run a full antimalware scan. This may reveal additional artifacts left in the system, persistence mechanisms, and malware components.
+- Determine the initial vector abused by the attacker and take action to prevent reinfection through the same vector.
+- Using the incident response data, update logging and audit policies to improve the mean time to detect (MTTD) and the mean time to respond (MTTR).
+"""
+references = ["https://www.cybercrimeinfocenter.org/top-20-tlds-by-malicious-phishing-domains"]
+risk_score = 73
+rule_id = "e516bf56-d51b-43e8-91ec-9e276331f433"
+severity = "high"
+tags = [
+    "Domain: Endpoint",
+    "OS: Windows",
+    "Use Case: Threat Detection",
+    "Tactic: Command and Control",
+    "Resources: Investigation Guide",
+    "Data Source: Elastic Endgame",
+    "Data Source: Elastic Defend",
+    "Data Source: Windows Security Event Logs",
+    "Data Source: SentinelOne",
+    "Data Source: Crowdstrike",
+    "Data Source: Sysmon",
+]
+timestamp_override = "event.ingested"
+type = "eql"
+
+query = '''
+network where host.os.type == "windows" and dns.question.name != null and
+ (
+  process.name : ("MSBuild.exe", "mshta.exe", "wscript.exe", "powershell.exe", "pwsh.exe", "msiexec.exe", "rundll32.exe",
+                  "bitsadmin.exe", "InstallUtil.exe", "python.exe", "regsvr32.exe", "dllhost.exe", "node.exe",
+                  "java.exe", "javaw.exe", "*.pif", "*.com", "*.scr") or
+  ?process.code_signature.exists == false or ?process.code_signature.trused == false or
+  ?process.code_signature.subject_name in ("AUTOIT CONSULTING LTD", "AutoIt Consulting Ltd", "OpenJS Foundation", "Python Software Foundation") or
+  process.executable : ("?:\\Users\\*.exe", "", "?:\\ProgramData\\*.exe",  "?\\Device\\HarddiskVolume?\\Users\\*.exe",  "?\\Device\\HarddiskVolume?\\ProgramData\\*.exe")
+ ) and
+dns.question.name regex """.*\.(top|buzz|xyz|rest|ml|cf|gq|ga|onion|monster|cyou|quest|cc|bar|cfd|click|cam|surf|tk|shop|club|icu|pw|ws|online|fun|life|boats|store|hair|skin|motorcycles|christmas|lol|makeup|mom|bond|beauty|biz|live|work|zip|country|accountant|date|party|science|loan|win|men|faith|review|racing|download|host)"""
+'''
+
+
+[[rule.threat]]
+framework = "MITRE ATT&CK"
+[[rule.threat.technique]]
+id = "T1071"
+name = "Application Layer Protocol"
+reference = "https://attack.mitre.org/techniques/T1071/"
+[[rule.threat.technique.subtechnique]]
+id = "T1071.004"
+name = "DNS"
+reference = "https://attack.mitre.org/techniques/T1071/004/"
+
+
+[rule.threat.tactic]
+id = "TA0011"
+name = "Command and Control"
+reference = "https://attack.mitre.org/tactics/TA0011/"
+
+

rules/windows/command_and_control_remcos_rat_iocs.toml

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+[metadata]
+creation_date = "2025/08/20"
+integration = ["endpoint", "windows", "sentinel_one_cloud_funnel", "m365_defender", "system"]
+maturity = "production"
+updated_date = "2025/08/20"
+
+[rule]
+author = ["Elastic"]
+description = """
+Identifies known execution traces of the REMCOS Remote Access Trojan. Remcos RAT is used by attackers to perform actions on infected machines remotely.
+"""
+from = "now-9m"
+index = [
+    "endgame-*",
+    "logs-endpoint.events.registry-*",
+    "logs-endpoint.events.file-*",
+    "logs-m365_defender.event-*",
+    "logs-sentinel_one_cloud_funnel.*",
+    "logs-system.security*",
+    "logs-windows.sysmon_operational-*",
+    "winlogbeat-*",
+]
+language = "eql"
+license = "Elastic License v2"
+name = "Potential REMCOS Trojan Execution"
+note = """## Triage and analysis
+
+### Investigating Potential REMCOS Trojan Execution
+
+Remcos RAT is used by attackers to perform actions on infected machines remotely.
+
+### Possible investigation steps
+
+- Review the origin of the REMCOS file and the execution chain to identify the initial vector..
+- Examine if the process is set to persist in the affected system via scheduled task, Startup folder or Run key.
+- Check the network, files and child processes activity associated with the every suspicious process in the execution chain of REMCOS.
+- Correlate the event with other security alerts or logs from data sources like Elastic Defend or Microsoft Defender for Endpoint to gather additional context and identify any related malicious activities.
+
+### Response and remediation
+
+- Immediately isolate the affected system from the network to prevent further unauthorized access or lateral movement by the attacker.
+- Terminate any suspicious processes identified in the alert, such as PowerShell, cmd.exe, or other flagged executables, to halt any ongoing malicious activity.
+- Review and revoke any unauthorized user accounts or privileges that may have been created or modified using tools like net.exe or schtasks.exe.
+- Conduct a thorough scan of the affected system using endpoint protection tools to identify and remove any malware or unauthorized software installed by the attacker.
+- Restore the system from a known good backup if any critical system files or configurations have been altered or compromised.
+- Escalate the incident to the security operations center (SOC) or incident response team for further investigation and to determine if additional systems are affected.
+- Implement enhanced monitoring and logging for ScreenConnect and other remote access tools to detect similar activities in the future, ensuring that alerts are promptly reviewed and acted upon."""
+references = [
+  "https://any.run/malware-trends/remcos",
+  "https://attack.mitre.org/software/S0332/",
+  "https://www.elastic.co/security-labs/exploring-the-ref2731-intrusion-set"
+]
+risk_score = 73
+rule_id = "d8b2f85a-cf1c-40fc-acf0-bb5d588a8ea6"
+severity = "high"
+tags = [
+    "Domain: Endpoint",
+    "OS: Windows",
+    "Use Case: Threat Detection",
+    "Tactic: Command and Control",
+    "Resources: Investigation Guide",
+    "Data Source: Elastic Endgame",
+    "Data Source: Elastic Defend",
+    "Data Source: Sysmon",
+    "Data Source: SentinelOne",
+    "Data Source: Microsoft Defender for Endpoint",
+    "Data Source: Windows Security Event Logs"
+]
+timestamp_override = "event.ingested"
+type = "eql"
+
+query = '''
+any where host.os.type == "windows" and
+(
+ (event.category == "file" and event.type == "deletion" and file.path like "C:\\Users\\*\\AppData\\Local\\Temp\\TH????.tmp") or
+
+ (event.category == "file" and file.path : "?:\\Users\\*\\AppData\\Roaming\\remcos\\logs.dat") or
+
+ (event.category == "registry" and
+  registry.path : (
+      "H*\\Windows\\CurrentVersion\\Run\\Remcos",
+      "H*\\Windows\\CurrentVersion\\Run\\Rmc-??????",
+      "H*\\SOFTWARE\\Remcos-*\\licence",
+      "H*\\Software\\Rmc-??????\\licence"
+      ))
+)
+'''
+
+
+[[rule.threat]]
+framework = "MITRE ATT&CK"
+[[rule.threat.technique]]
+id = "T1219"
+name = "Remote Access Tools"
+reference = "https://attack.mitre.org/techniques/T1219/"
+
+
+[rule.threat.tactic]
+id = "TA0011"
+name = "Command and Control"
+reference = "https://attack.mitre.org/tactics/TA0011/"
+

rules/windows/command_and_control_rmm_netsupport_susp_path.toml

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+[metadata]
+creation_date = "2025/08/20"
+integration = ["endpoint", "windows", "sentinel_one_cloud_funnel", "m365_defender", "system", "crowdstrike"]
+maturity = "production"
+updated_date = "2025/08/20"
+
+[rule]
+author = ["Elastic"]
+description = """
+Identifies execution of the NetSupport remote access software from non-default paths. Adversaries may abuse NetSupport
+Manager to control a target victim machine.
+"""
+from = "now-9m"
+index = [
+    "endgame-*",
+    "logs-crowdstrike.fdr*",
+    "logs-endpoint.events.process-*",
+    "logs-m365_defender.event-*",
+    "logs-sentinel_one_cloud_funnel.*",
+    "logs-system.security*",
+    "logs-windows.sysmon_operational-*",
+    "winlogbeat-*",
+]
+language = "eql"
+license = "Elastic License v2"
+name = "NetSupport Manager Execution from an Unusual Path"
+note = """## Triage and analysis
+
+### Investigating NetSupport Manager Execution from an Unusual Path
+
+NetSupport Manager, is a remote access tool, facilitates legitimate remote support but can be exploited by adversaries to execute unauthorized commands.
+
+### Possible investigation steps
+
+- Review the origin of the NetSupport file and if it's related to an authorized IT Support case.
+- Examine if the NetSupport process is set to persist in the affected system via scheduled task, Startup folder or Run key.
+- Check the network, files and child processes activity associated with the NetSupport client32.exe process.
+- Correlate the event with other security alerts or logs from data sources like Elastic Defend or Microsoft Defender for Endpoint to gather additional context and identify any related malicious activities.
+
+### False positive analysis
+
+- Legitimate IT support activities using NetSupport by IT support accounts.
+
+### Response and remediation
+
+- Immediately isolate the affected system from the network to prevent further unauthorized access or lateral movement by the attacker.
+- Terminate any suspicious processes identified in the alert, such as PowerShell, cmd.exe, or other flagged executables, to halt any ongoing malicious activity.
+- Review and revoke any unauthorized user accounts or privileges that may have been created or modified using tools like net.exe or schtasks.exe.
+- Conduct a thorough scan of the affected system using endpoint protection tools to identify and remove any malware or unauthorized software installed by the attacker.
+- Restore the system from a known good backup if any critical system files or configurations have been altered or compromised.
+- Escalate the incident to the security operations center (SOC) or incident response team for further investigation and to determine if additional systems are affected.
+- Implement enhanced monitoring and logging for ScreenConnect and other remote access tools to detect similar activities in the future, ensuring that alerts are promptly reviewed and acted upon."""
+references = [
+    "https://www.netsupportsoftware.com/",
+]
+risk_score = 73
+rule_id = "5f73aef2-7abc-4fd9-ac0d-ab8ec3e13891"
+severity = "high"
+tags = [
+    "Domain: Endpoint",
+    "OS: Windows",
+    "Use Case: Threat Detection",
+    "Tactic: Command and Control",
+    "Resources: Investigation Guide",
+    "Data Source: Elastic Endgame",
+    "Data Source: Elastic Defend",
+    "Data Source: Sysmon",
+    "Data Source: SentinelOne",
+    "Data Source: Microsoft Defender for Endpoint",
+    "Data Source: Windows Security Event Logs",
+    "Data Source: Crowdstrike",
+]
+timestamp_override = "event.ingested"
+type = "eql"
+
+query = '''
+process where host.os.type == "windows" and event.type == "start" and
+ (process.name : "client32.exe" or ?process.pe.original_file_name == "client32.exe" or process.parent.name : "client32.exe") and
+ (
+  process.executable :
+               ("?:\\Users\\*.exe",
+                "?:\\ProgramData\\*.exe",
+                "\\Device\\HarddiskVolume?\\Users\\*.exe",
+                "\\Device\\HarddiskVolume?\\ProgramData\\*.exe") or
+  ?process.parent.executable : ("?:\\Users\\*\\client32.exe", "?:\\ProgramData\\*\\client32.exe")
+  )
+'''
+
+
+[[rule.threat]]
+framework = "MITRE ATT&CK"
+[[rule.threat.technique]]
+id = "T1219"
+name = "Remote Access Tools"
+reference = "https://attack.mitre.org/techniques/T1219/"
+
+
+[rule.threat.tactic]
+id = "TA0011"
+name = "Command and Control"
+reference = "https://attack.mitre.org/tactics/TA0011/"
+