Windows Process Creation Indicators for PowerShell MSI Download and Silent Install (PaperCut MF/NG)

Detects hidden PowerShell downloading a setup.msi and silent msiexec installation tied to PaperCut MF/NG exploitation indicators.

FreeReviewedSigma · High · v5
Product
windows
Category
process_creation
Author
Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2023-04-25
Updated
2026-07-31

What it detects

This rule identifies Windows process creation activity where PowerShell is invoked with hidden/no-profile execution to download a MSI via Invoke-WebRequest and save it to setup.msi. It further matches msiexec running a silent installation of the same MSI with a specific IntegratorLogin parameter. These behaviors matter because they align with automated exploitation chains that stage and install attacker-controlled components with minimal user visibility. The detection relies on process creation telemetry with full command-line arguments, including PowerShell and msiexec command parameters.

Changelog

v5
  1. v5
    Candidate ingested via manual entry.2026-07-31
  2. v4
    Candidate ingested via manual entry.2026-07-31
  3. v3
    Candidate ingested via manual entry.2026-07-31
  4. v2
    Candidate ingested via manual entry.2026-07-31
  5. v1
    No changelog recorded for this version.2026-07-30

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.