ID | Technique | Tactic |
---|---|---|
T1562 | Impair Defenses | Defense Evasion |
T1562.002 | Disable Windows Event Logging | Defense Evasion |
T1505 | Server Software Component | Persistence |
T1505.004 | IIS Components | Persistence |
Detection: Windows PowerShell Disable HTTP Logging
Description
The following analytic detects the use of get-WebConfigurationProperty
and Set-ItemProperty
commands in PowerShell to disable HTTP logging on Windows systems. This detection leverages PowerShell Script Block Logging, specifically looking for script blocks that reference HTTP logging properties and attempt to set them to "false" or "dontLog". Disabling HTTP logging is significant as it can be used by adversaries to cover their tracks and delete logs, hindering forensic investigations. If confirmed malicious, this activity could allow attackers to evade detection and persist in the environment undetected.
Search
1`powershell` EventCode=4104 ScriptBlockText IN("*get-WebConfigurationProperty*","*Set-ItemProperty*") AND ScriptBlockText IN ("*httpLogging*","*Logfile.enabled*") AND ScriptBlockText IN ("*dontLog*", "*false*")
2| stats count min(_time) as firstTime max(_time) as lastTime by EventCode ScriptBlockText Computer user_id
3| `security_content_ctime(firstTime)`
4| `security_content_ctime(lastTime)`
5| `windows_powershell_disable_http_logging_filter`
Data Source
Name | Platform | Sourcetype | Source |
---|---|---|---|
Powershell Script Block Logging 4104 | Windows | 'xmlwineventlog' |
'XmlWinEventLog:Microsoft-Windows-PowerShell/Operational' |
Macros Used
Name | Value |
---|---|
powershell | (source=WinEventLog:Microsoft-Windows-PowerShell/Operational OR source="XmlWinEventLog:Microsoft-Windows-PowerShell/Operational") |
windows_powershell_disable_http_logging_filter | search * |
windows_powershell_disable_http_logging_filter
is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Annotations
Default Configuration
This detection is configured by default in Splunk Enterprise Security to run with the following settings:
Setting | Value |
---|---|
Disabled | true |
Cron Schedule | 0 * * * * |
Earliest Time | -70m@m |
Latest Time | -10m@m |
Schedule Window | auto |
Creates Notable | Yes |
Rule Title | %name% |
Rule Description | %description% |
Notable Event Fields | user, dest |
Creates Risk Event | True |
Implementation
To successfully implement this analytic, you will need to enable PowerShell Script Block Logging on some or all endpoints. Additional setup here https://docs.splunk.com/Documentation/UBA/5.0.4.1/GetDataIn/AddPowerShell#Configure_module_logging_for_PowerShell.
Known False Positives
It is possible administrators or scripts may run these commands, filtering may be required.
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
A PowerShell Cmdlet related to disable or modifying a IIS HTTP logging has occurred on $Computer$. | 64 | 80 | 80 |
References
Detection Testing
Test Type | Status | Dataset | Source | Sourcetype |
---|---|---|---|---|
Validation | ✅ Passing | N/A | N/A | N/A |
Unit | ✅ Passing | Dataset | XmlWinEventLog:Microsoft-Windows-PowerShell/Operational |
XmlWinEventLog |
Integration | ✅ Passing | Dataset | XmlWinEventLog:Microsoft-Windows-PowerShell/Operational |
XmlWinEventLog |
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: GitHub | Version: 3