Try in Splunk Security Cloud

Description

The following analytic leverages events 4625 and 4624 to identify an endpoint using the builtin local Administrator account to authenticate to a large numbers of endpoints. Specifically, the logic will trigger when an endpoints attempts to authenticate to more than 30 target computers within a 5 minute timespan. This behavior could represent an adversary who has obtained access to local credentials and is trying to validate if these credentials work on other hosts to escalate their privileges. As environments differ across organizations, security teams should customize the thresholds of this detection as needed.

  • Type: TTP

  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud

  • Last Updated: 2023-03-22
  • Author: Mauricio Velazco, Splunk
  • ID: 09555511-aca6-484a-b6ab-72cd03d73c34

Annotations

ATT&CK

ATT&CK

ID Technique Tactic
T1110 Brute Force Credential Access
T1110.004 Credential Stuffing Credential Access
Kill Chain Phase
  • Exploitation
NIST
  • DE.CM
CIS20
  • CIS 10
CVE 


1
2
3
4
5



 `wineventlog_security` EventCode=4625 OR EventCode=4624 Logon_Type=3 TargetUserName=Administrator 
| bucket span=5m _time 
| stats dc(Computer) AS unique_targets values(Computer) as host_targets by _time, IpAddress, TargetUserName, EventCode 
| where unique_targets > 30 
| `windows_local_administrator_credential_stuffing_filter`

Macros

The SPL above uses the following Macros:

:information_source: windows_local_administrator_credential_stuffing_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Required fields

List of fields required to use this analytic.

  • _time
  • EventCode
  • Logon_Type
  • TargetUserName
  • Computer
  • IpAddress

How To Implement

To successfully implement this search, you need to be ingesting Windows Event Logs from domain controllers as well as member servers and workstations. The Advanced Security Audit policy setting Audit Logon within Logon/Logoff needs to be enabled.

Known False Positives

Vulnerability scanners or system administration tools may also trigger this detection. Filter as needed.

Associated Analytic Story

RBA

Risk Score Impact Confidence Message
56.0 70 80 Local Administrator credential stuffing attack coming from $IpAddress$

:information_source: The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

Reference

Test Dataset

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

source | version: 1