Suspicious Expensive LDAP Query Reconnaissance

ATT&CK techniques

Discovery

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
- T1087.002Domain Account
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects Directory Service event 1644 recording expensive or inefficient LDAP search queries against a domain controller. This behavior matches LDAP-based reconnaissance where attackers issue broad filters to enumerate users, groups, and computers. A burst of expensive LDAP queries from unusual sources indicates active directory enumeration and should be correlated with the requesting host.

Reporting behind it

Related detections9 linkedT1087.002 — drag to rearrange

Malicious Active Directory Enumeration via SharpHound or BloodHound (via process_creation)

Suspicious Group Discovery - Command (via process_creation)

SharpHound Host Enumeration Over Kerberos (via security)

SPN Enumeration Previous to Kerberoasting Attack - Native Commands (via process_creation)

Suspicious Active Directory Enumeration via AD Explorer Snapshot Process Creation

Malicious Account Added to Domain Admins Group via net Command

Suspicious Remote Connection to ADWS Port 9389 via security

Suspicious Octo Tempest Domain and Network Reconnaissance Tooling (via process_creation)

Suspicious Active Directory Computer Export via csvde (via process_creation)

Suspicious Expensive LDAP Query Reconnaissance

Pivot detection · T1087.002 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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