LoFP LoFP / although unlikely, some legitimate applications may use a moved copy of microsoft.workflow.compiler.exe, triggering a false positive.

Techniques

Sample rules

Suspicious microsoft workflow compiler rename

Description

The following analytic detects the renaming of microsoft.workflow.compiler.exe, a rarely used executable typically located in C:\Windows\Microsoft.NET\Framework64\v4.0.30319. This detection leverages Endpoint Detection and Response (EDR) data, focusing on process names and original file names. This activity is significant because renaming this executable can indicate an attempt to evade security controls. If confirmed malicious, an attacker could use this renamed executable to execute arbitrary code, potentially leading to privilege escalation or persistent access within the environment.

Detection logic


| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.process_name!=microsoft.workflow.compiler.exe AND Processes.original_file_name=Microsoft.Workflow.Compiler.exe by Processes.dest Processes.user Processes.parent_process_name Processes.process_name Processes.process Processes.process_id Processes.parent_process_id Processes.original_file_name 
| `drop_dm_object_name(Processes)` 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| `suspicious_microsoft_workflow_compiler_rename_filter`