Detection rules › Splunk

Windows Local Administrator Credential Stuffing

Status
production
Severity
medium
Group by
_time, action, app, authentication_method, signature, signature_id, src_ip, user
Author
Mauricio Velazco, Splunk
Source
github.com/splunk/security_content

The following analytic detects attempts to authenticate using the built-in local Administrator account across more than 30 endpoints within a 5-minute window. It leverages Windows Event Logs, specifically events 4625 and 4624, to identify this behavior. This activity is significant as it may indicate an adversary attempting to validate stolen local credentials across multiple hosts, potentially leading to privilege escalation. If confirmed malicious, this could allow the attacker to gain widespread access and control over numerous systems within the network, posing a severe security risk.

Known false positives

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

MITRE ATT&CK coverage

TacticTechniques
Credential Access

Telemetry coverage

Rule body

name: Windows Local Administrator Credential Stuffing
id: 09555511-aca6-484a-b6ab-72cd03d73c34
version: 13
creation_date: '2023-03-22'
modification_date: '2026-05-13'
author: Mauricio Velazco, Splunk
status: production
type: TTP
description: The following analytic detects attempts to authenticate using the built-in local Administrator account across more than 30 endpoints within a 5-minute window. It leverages Windows Event Logs, specifically events 4625 and 4624, to identify this behavior. This activity is significant as it may indicate an adversary attempting to validate stolen local credentials across multiple hosts, potentially leading to privilege escalation. If confirmed malicious, this could allow the attacker to gain widespread access and control over numerous systems within the network, posing a severe security risk.
data_source:
    - Windows Event Log Security 4624
    - Windows Event Log Security 4625
search: |-
    `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 values(dest) as dest values(src) as src values(user) as user
        BY _time, IpAddress, TargetUserName,
           EventCode, action, app,
           authentication_method, signature, signature_id
      | where unique_targets > 30
      | `windows_local_administrator_credential_stuffing_filter`
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.
references:
    - https://attack.mitre.org/techniques/T1110/004/
    - https://attack.mitre.org/techniques/T1110/
    - https://www.blackhillsinfosec.com/wide-spread-local-admin-testing/
    - https://www.pentestpartners.com/security-blog/admin-password-re-use-dont-do-it/
    - https://www.praetorian.com/blog/microsofts-local-administrator-password-solution-laps/
    - https://wiki.porchetta.industries/smb-protocol/password-spraying
finding:
    title: Local Administrator credential stuffing attack coming from $IpAddress$
    entity:
        field: host_targets
        type: system
        score: 50
threat_objects:
    - field: IpAddress
      type: ip_address
analytic_story:
    - Active Directory Privilege Escalation
    - Active Directory Lateral Movement
    - Scattered Lapsus$ Hunters
asset_type: Endpoint
mitre_attack_id:
    - T1110.004
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint

Stages and Predicates

Stage 1: search

`wineventlog_security` EventCode=4625 OR EventCode=4624 Logon_Type=3 TargetUserName=Administrator

Stage 2: bucket

| bucket span=5m _time

Stage 3: stats

| stats dc(Computer) AS unique_targets values(Computer) as host_targets values(dest) as dest values(src) as src values(user) as user
    BY _time, IpAddress, TargetUserName,
       EventCode, action, app,
       authentication_method, signature, signature_id

Stage 4: where

| where unique_targets > 30

Stage 5: search

| `windows_local_administrator_credential_stuffing_filter`

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
EventCodeeq
  • 4624 corpus 29 (splunk 13, kusto 11, chronicle 4, elastic 1)
  • 4625 corpus 15 (splunk 11, chronicle 2, kusto 2)
field:"EventID" kind:eq
Logon_Typeeq
  • 3 corpus 41 (splunk 13, sigma 12, elastic 9, kusto 7)
field:"LogonType" kind:eq value:"3"
TargetUserNameeq
  • Administrator
field:"TargetUserName" kind:eq value:"Administrator"
unique_targetsgt
  • 30 corpus 5 (splunk 5)
field:"unique_targets" kind:gt value:"30"