Active Directory Discovery using AdExplorer

  1[metadata]
  2creation_date = "2025/09/01"
  3integration = ["endpoint", "windows", "system", "m365_defender", "sentinel_one_cloud_funnel", "crowdstrike"]
  4maturity = "production"
  5updated_date = "2026/05/04"
  6
  7[rule]
  8author = ["Elastic"]
  9description = """
 10This rule detects the use of ADExplorer utility. Active Directory Explorer (AD Explorer) is an advanced Active Directory (AD)
 11viewer and editor. AD Explorer also includes the ability to save snapshots of an AD database for off-line viewing and comparisons.
 12Adversaries may abuse this utility to perform domain reconnaissance.
 13"""
 14from = "now-9m"
 15index = [
 16    "endgame-*",
 17    "logs-crowdstrike.fdr*",
 18    "logs-endpoint.events.process-*",
 19    "logs-m365_defender.event-*",
 20    "logs-sentinel_one_cloud_funnel.*",
 21    "logs-system.security*",
 22    "logs-windows.forwarded*",
 23    "logs-windows.sysmon_operational-*",
 24    "winlogbeat-*",
 25]
 26language = "eql"
 27license = "Elastic License v2"
 28name = "Active Directory Discovery using AdExplorer"
 29note = """## Triage and analysis
 30
 31### Investigating Active Directory Discovery using AdExplorer
 32
 33Active Directory Explorer (AD Explorer) is an advanced Active Directory (AD) viewer and editor. AD Explorer also includes the ability to save snapshots of an AD database for off-line viewing and comparisons.
 34
 35#### Possible investigation steps
 36
 37- Identify the user account that performed the action and whether it should perform this kind of action.
 38- Verify any file creation, this may indicate the creation of an AD snapshot.
 39- Identify when the AdExplorer binary was dropped and by what process reviewing file creation events.
 40- Contact the account owner and confirm whether they are aware of this activity.
 41- Investigate other alerts associated with the user/host during the past 48 hours.
 42
 43### False positive analysis
 44
 45- This rule has a high chance to produce false positives as it is a legitimate tool used by system administrators.
 46- If this rule is noisy in your environment due to expected activity, consider adding exceptions — preferably with a combination of user and process path conditions.
 47
 48### Response and remediation
 49
 50- Initiate the incident response process based on the outcome of the triage.
 51- Isolate the involved host to prevent further post-compromise behavior.
 52- 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.
 53- Run a full antimalware scan. This may reveal additional artifacts left in the system, persistence mechanisms, and malware components.
 54- Determine the initial vector abused by the attacker and take action to prevent reinfection through the same vector.
 55- 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).
 56"""
 57
 58setup = """## Setup
 59
 60This rule is designed for data generated by [Elastic Defend](https://www.elastic.co/security/endpoint-security), which provides native endpoint detection and response, along with event enrichments designed to work with our detection rules.
 61
 62Setup instructions: https://ela.st/install-elastic-defend
 63
 64### Additional data sources
 65
 66This rule also supports the following third-party data sources. For setup instructions, refer to the links below:
 67
 68- [CrowdStrike](https://ela.st/crowdstrike-integration)
 69- [Microsoft Defender XDR](https://ela.st/m365-defender)
 70- [SentinelOne Cloud Funnel](https://ela.st/sentinel-one-cloud-funnel)
 71- [Sysmon Event ID 1 - Process Creation](https://ela.st/sysmon-event-1-setup)
 72- [Windows Process Creation Logs](https://ela.st/audit-process-creation)
 73"""
 74
 75references = ["https://learn.microsoft.com/en-us/sysinternals/downloads/adexplorer"]
 76risk_score = 21
 77rule_id = "ff46eb26-0684-4da3-9dd6-21032c9878e1"
 78severity = "low"
 79tags = [
 80    "Domain: Endpoint",
 81    "OS: Windows",
 82    "Use Case: Threat Detection",
 83    "Tactic: Discovery",
 84    "Resources: Investigation Guide",
 85    "Data Source: Elastic Endgame",
 86    "Data Source: Elastic Defend",
 87    "Data Source: Windows Security Event Logs",
 88    "Data Source: Microsoft Defender XDR",
 89    "Data Source: Sysmon",
 90    "Data Source: SentinelOne",
 91    "Data Source: Crowdstrike",
 92]
 93timestamp_override = "event.ingested"
 94type = "eql"
 95
 96query = '''
 97process where host.os.type == "windows" and event.type == "start" and
 98  (process.name : "ADExplorer*.exe" or ?process.pe.original_file_name == "AdExp")
 99'''
100
101
102[[rule.threat]]
103framework = "MITRE ATT&CK"
104[[rule.threat.technique]]
105id = "T1016"
106name = "System Network Configuration Discovery"
107reference = "https://attack.mitre.org/techniques/T1016/"
108
109[[rule.threat.technique]]
110id = "T1018"
111name = "Remote System Discovery"
112reference = "https://attack.mitre.org/techniques/T1018/"
113
114[[rule.threat.technique]]
115id = "T1069"
116name = "Permission Groups Discovery"
117reference = "https://attack.mitre.org/techniques/T1069/"
118[[rule.threat.technique.subtechnique]]
119id = "T1069.002"
120name = "Domain Groups"
121reference = "https://attack.mitre.org/techniques/T1069/002/"
122
123
124[[rule.threat.technique]]
125id = "T1087"
126name = "Account Discovery"
127reference = "https://attack.mitre.org/techniques/T1087/"
128[[rule.threat.technique.subtechnique]]
129id = "T1087.002"
130name = "Domain Account"
131reference = "https://attack.mitre.org/techniques/T1087/002/"
132
133
134[[rule.threat.technique]]
135id = "T1482"
136name = "Domain Trust Discovery"
137reference = "https://attack.mitre.org/techniques/T1482/"
138
139
140[rule.threat.tactic]
141id = "TA0007"
142name = "Discovery"
143reference = "https://attack.mitre.org/tactics/TA0007/"