LoFP / administrators may legitimately use applocker to allow applications.

Techniques

• T1218

Sample rules

Windows AppLocker Block Events

• source: splunk
• technicques:
  • T1218

Description

The following analytic detects attempts to bypass application restrictions by identifying Windows AppLocker policy violations. It leverages Windows AppLocker event logs, specifically EventCodes 8007, 8004, 8022, 8025, 8029, and 8040, to pinpoint blocked actions. This activity is significant for a SOC as it highlights potential unauthorized application executions, which could indicate malicious intent or policy circumvention. If confirmed malicious, this activity could allow an attacker to execute unauthorized applications, potentially leading to further system compromise or data exfiltration.

Detection logic

`applocker`  EventCode IN (8007, 8004, 8022, 8025, 8029, 8040) 
| spath input=UserData_Xml 
| rename RuleAndFileData.* as *, TargetUser as user, Computer as dest  
| stats count min(_time) as firstTime max(_time) as lastTime by dest, PolicyName, RuleId, user, TargetProcessId, FilePath, FullFilePath, EventCode 
| lookup applockereventcodes EventCode OUTPUT Description 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| `windows_applocker_block_events_filter`