Detection rules › Splunk
Windows Powershell Logoff User via Quser
The following analytic detects the process of logging off a user through the use of the quser and logoff commands. By monitoring for these commands, the analytic identifies actions where a user session is forcibly terminated, which could be part of an administrative task or a potentially unauthorized access attempt. This detection helps identify potential misuse or malicious activity where a user's access is revoked without proper authorization, providing insight into potential security incidents involving account management or session manipulation.
Known false positives
- Administrators or power users may use this command.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Execution | |
| Impact |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| PowerShell | Event ID 4104: Creating Scriptblock text (MessageNumber of MessageTotal). |
Rule body
name: Windows Powershell Logoff User via Quser
id: 6d70780d-4cfe-4820-bafd-1b43941986b5
version: 9
creation_date: '2024-12-13'
modification_date: '2026-06-29'
author: Teoderick Contreras, Splunk
status: production
type: Anomaly
description: |-
The following analytic detects the process of logging off a user through the use of the quser and logoff commands.
By monitoring for these commands, the analytic identifies actions where a user session is forcibly terminated, which could be part of an administrative task or a potentially unauthorized access attempt.
This detection helps identify potential misuse or malicious activity where a user's access is revoked without proper authorization, providing insight into potential security incidents involving account management or session manipulation.
data_source:
- Powershell Script Block Logging 4104
search: |-
`powershell`
EventCode=4104
ScriptBlockText = "*quser*logoff*"
| fillnull
| stats count min(_time) as firstTime
max(_time) as lastTime
by dest signature signature_id
user_id vendor_product EventID
Guid Opcode Name
Path ProcessID ScriptBlockId
ScriptBlockText
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_powershell_logoff_user_via_quser_filter`
how_to_implement: The following Hunting analytic requires PowerShell operational logs to be imported. Modify the powershell macro as needed to match the sourcetype or add index. This analytic is specific to 4104, or PowerShell Script Block Logging.
known_false_positives: Administrators or power users may use this command.
references:
- https://devblogs.microsoft.com/scripting/automating-quser-through-powershell/
intermediate_findings:
entities:
- field: dest
type: system
score: 20
message: A suspicious powershell script with the ScriptBlockId [$ScriptBlockId$] containing quser and logoff commands to potentially logoff user was executed on host $dest$
- field: user_id
type: user
score: 20
message: A suspicious powershell script with the ScriptBlockId [$ScriptBlockId$] containing quser and logoff commands to potentially logoff user was executed on host $dest$ by user $user_id$
analytic_story:
- Crypto Stealer
asset_type: Endpoint
mitre_attack_id:
- T1059.001
- T1531
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
category: endpoint
security_domain: endpoint
Stages and Predicates
Stage 1: search
`powershell`
EventCode=4104
ScriptBlockText = "*quser*logoff*"
Stage 2: fillnull
| fillnull
Stage 3: stats
| stats count min(_time) as firstTime
max(_time) as lastTime
by dest signature signature_id
user_id vendor_product EventID
Guid Opcode Name
Path ProcessID ScriptBlockId
ScriptBlockText
Stage 4: search
| `security_content_ctime(firstTime)`
Stage 5: search
| `security_content_ctime(lastTime)`
Stage 6: search
| `windows_powershell_logoff_user_via_quser_filter`
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
EventCode | eq |
| field:"EventID" kind:eq value:"4104" |
ScriptBlockText | eq |
| field:"ScriptBlockText" kind:eq |