Back to results

UMWorkerProcess Creating Webshell

This query detects unusual file content created by UMWorkerProcess, indicating exploitation of CVE-2021-26858 to generate a web shell. More related queries can be found on the Microsoft Security Response Center blog.

Detection logic

Detection requirements

Log source product
microsoftthreatprotection
Log source service
devicefileevents

Detections can measure how the public catalogue is used — which detections people look for, and which pages bring them here. It sets a cookie that recognises this browser for 180 days. It is never linked to an account and never follows you to other sites. Privacy notice