Windows Administrative Shares Accessed On Multiple Hosts

name: Windows Administrative Shares Accessed On Multiple Hosts
id: d92f2d95-05fb-48a7-910f-4d3d61ab8655
version: 10
creation_date: '2023-03-23'
modification_date: '2026-05-13'
author: Mauricio Velazco, Splunk
status: production
type: TTP
description: The following analytic detects a source computer accessing Windows administrative shares (C$, Admin$, IPC$) on 30 or more remote endpoints within a 5-minute window. It leverages Event IDs 5140 and 5145 from file share events. This behavior is significant as it may indicate an adversary enumerating network shares to locate sensitive files, a common tactic used by threat actors. If confirmed malicious, this activity could lead to unauthorized access to critical data, lateral movement, and potential compromise of multiple systems within the network.
data_source:
    - Windows Event Log Security 5140
    - Windows Event Log Security 5145
search: '`wineventlog_security` EventCode=5140 OR EventCode=5145 (ShareName="\\\\*\\ADMIN$" OR ShareName="\\\\*\\IPC$" OR ShareName="\\\\*\\C$") | bucket span=5m _time | stats dc(Computer) AS unique_targets values(Computer) as host_targets values(ShareName) as shares values(dest) as dest by _time, IpAddress, SubjectUserName, EventCode | where unique_targets > 30 | `windows_administrative_shares_accessed_on_multiple_hosts_filter`'
how_to_implement: To successfully implement this search, you need to be ingesting file share events. The Advanced Security Audit policy setting `Audit Detailed File Share` or `Audit File Share` within `Object Access` need to be enabled.
known_false_positives: An single endpoint accessing windows administrative shares across a large number of endpoints is not common behavior. Possible false positive scenarios include but are not limited to vulnerability scanners, administration systems and missconfigured systems.
references:
    - https://attack.mitre.org/techniques/T1135/
    - https://en.wikipedia.org/wiki/Administrative_share
    - https://thedfirreport.com/2023/01/23/sharefinder-how-threat-actors-discover-file-shares/
    - https://learn.microsoft.com/en-us/windows/security/threat-protection/auditing/event-5140
    - https://learn.microsoft.com/en-us/windows/security/threat-protection/auditing/event-5145
drilldown_searches:
    - name: View the detection results for - "$host_targets$"
      search: '%original_detection_search% | search  host_targets = "$host_targets$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$host_targets$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$host_targets$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
      earliest_offset: 7d
      latest_offset: "0"
finding:
    title: $IpAddress$ accessed the IPC share on more than 30 endpoints in a timespan of 5 minutes.
    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
asset_type: Endpoint
mitre_attack_id:
    - T1135
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1135/ipc_share_accessed/windows-security.log
          source: XmlWinEventLog:Security
          sourcetype: XmlWinEventLog
      test_type: unit