« NTDS Dump via Wbadmin Namespace Manipulation Using Unshare »
Elastic Docs ›Elastic Security Solution [8.16] ›Detections and alerts ›Prebuilt rule reference

NTDS or SAM Database File Copied

edit

NTDS or SAM Database File Copied

edit

Identifies a copy operation of the Active Directory Domain Database (ntds.dit) or Security Account Manager (SAM) files. Those files contain sensitive information including hashed domain and/or local credentials.

Rule type: eql

Rule indices:

  • winlogbeat-*
  • logs-endpoint.events.process-*
  • logs-windows.forwarded*
  • logs-windows.sysmon_operational-*
  • endgame-*
  • logs-system.security*
  • logs-m365_defender.event-*
  • logs-sentinel_one_cloud_funnel.*
  • logs-crowdstrike.fdr*

Severity: high

Risk score: 73

Runs every: 5m

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 33

References:

Tags:

  • Domain: Endpoint
  • OS: Windows
  • Use Case: Threat Detection
  • Tactic: Credential Access
  • Data Source: Elastic Endgame
  • Data Source: Elastic Defend
  • Data Source: System
  • Data Source: Microsoft Defender for Endpoint
  • Data Source: SentinelOne
  • Data Source: Sysmon
  • Data Source: Crowdstrike

Version: 315

Rule authors:

  • Elastic
  • Austin Songer

Rule license: Elastic License v2

Investigation guide

edit

Triage and analysis

Investigating NTDS or SAM Database File Copied

The Active Directory Domain Database (ntds.dit) and Security Account Manager (SAM) files are critical components in Windows environments, containing sensitive information such as hashed domain and local credentials.

This rule identifies copy operations of these files using specific command-line tools, such as Cmd.Exe, PowerShell.EXE, XCOPY.EXE, and esentutl.exe. By monitoring for the presence of these tools and their associated arguments, the rule aims to detect potential credential access activities.

Note: This investigation guide uses the Osquery Markdown Plugin introduced in Elastic Stack version 8.5.0. Older Elastic Stack versions will display unrendered Markdown in this guide.

Possible investigation steps

  • Investigate the process execution chain (parent process tree) for unknown processes. Examine their executable files for prevalence, command lines, whether they are located in expected locations, and if they are signed with valid digital signatures.
  • Identify the user account that performed the action and whether it should perform this kind of action.
  • Contact the account owner and confirm whether they are aware of this activity.
  • Investigate other alerts associated with the user/host during the past 48 hours.
  • Check for any recent changes in user account privileges or group memberships that may have allowed the unauthorized access.
  • Determine whether the file was potentially exfiltrated from the subject host.
  • Scope compromised credentials and disable the accounts.
  • Examine the host for derived artifacts that indicate suspicious activities:
  • Analyze the process executable using a private sandboxed analysis system.
  • Observe and collect information about the following activities in both the sandbox and the alert subject host:
  • Attempts to contact external domains and addresses.
  • Use the Elastic Defend network events to determine domains and addresses contacted by the subject process by filtering by the process’s process.entity_id.
  • Examine the DNS cache for suspicious or anomalous entries.
  • !{osquery{"label":"Osquery - Retrieve DNS Cache","query":"SELECT * FROM dns_cache"}}
  • Use the Elastic Defend registry events to examine registry keys accessed, modified, or created by the related processes in the process tree.
  • Examine the host services for suspicious or anomalous entries.
  • !{osquery{"label":"Osquery - Retrieve All Services","query":"SELECT description, display_name, name, path, pid, service_type, start_type, status, user_account FROM services"}}
  • !{osquery{"label":"Osquery - Retrieve Services Running on User Accounts","query":"SELECT description, display_name, name, path, pid, service_type, start_type, status, user_account FROM services WHERE\nNOT (user_account LIKE %LocalSystem OR user_account LIKE %LocalService OR user_account LIKE %NetworkService OR\nuser_account == null)\n"}}
  • !{osquery{"label":"Osquery - Retrieve Service Unsigned Executables with Virustotal Link","query":"SELECT concat(https://www.virustotal.com/gui/file/, sha1) AS VtLink, name, description, start_type, status, pid,\nservices.path FROM services JOIN authenticode ON services.path = authenticode.path OR services.module_path =\nauthenticode.path JOIN hash ON services.path = hash.path WHERE authenticode.result != trusted\n"}}
  • Retrieve the files' SHA-256 hash values using the PowerShell Get-FileHash cmdlet and search for the existence and reputation of the hashes in resources like VirusTotal, Hybrid-Analysis, CISCO Talos, Any.run, etc.
  • Look for the presence of relevant artifacts on other systems. Identify commonalities and differences between potentially compromised systems.

False positive analysis

  • This activity is unlikely to happen legitimately. Benign true positives (B-TPs) can be added as exceptions if necessary.

Response and Remediation

  • Initiate the incident response process based on the outcome of the triage.
  • If malicious activity is confirmed, perform a broader investigation to identify the scope of the compromise and determine the appropriate remediation steps.
  • Isolate the involved hosts to prevent further post-compromise behavior.
  • If the triage identified malware, search the environment for additional compromised hosts.
  • Implement temporary network rules, procedures, and segmentation to contain the malware.
  • Stop suspicious processes.
  • Immediately block the identified indicators of compromise (IoCs).
  • Inspect the affected systems for additional malware backdoors like reverse shells, reverse proxies, or droppers that attackers could use to reinfect the system.
  • Remove and block malicious artifacts identified during triage.
  • Restore the affected system to its operational state by applying any necessary patches, updates, or configuration changes.
  • 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.
  • 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).

Rule query

edit
process where host.os.type == "windows" and event.type == "start" and
  (
    ((?process.pe.original_file_name in ("Cmd.Exe", "PowerShell.EXE", "XCOPY.EXE") or process.name : ("Cmd.Exe", "PowerShell.EXE", "XCOPY.EXE")) and
       process.args : ("copy", "xcopy", "Copy-Item", "move", "cp", "mv")
    ) or
    ((?process.pe.original_file_name : "esentutl.exe" or process.name : "esentutl.exe") and process.args : ("*/y*", "*/vss*", "*/d*"))
  ) and
  process.command_line : ("*\\ntds.dit*", "*\\config\\SAM*", "*\\*\\GLOBALROOT\\Device\\HarddiskVolumeShadowCopy*\\*", "*/system32/config/SAM*", "*\\User Data\\*")

Framework: MITRE ATT&CKTM

« NTDS Dump via Wbadmin Namespace Manipulation Using Unshare »