Windows Code Integrity blocked disallowed file for protected processes (Event ID 3104)

Alerts on Windows Code Integrity Event ID 3104 when a disallowed file is blocked for protected processes.

FreeReviewedSigma · High · v2
Product
windows
Service
codeintegrity-operational
Author
Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2023-06-06
Updated
2026-07-31

What it detects

This rule flags Windows Code Integrity block events where a file is denied because it is disallowed for protected processes. Such blocking is significant because it prevents execution of binaries that do not meet the protection policy, which attackers may try to bypass via unauthorized or untrusted executables. The detection relies on Code Integrity operational logs capturing Event ID 3104, including the blocked-file context.

Changelog

v2
  1. v2
    Candidate ingested via manual entry.2026-07-31
  2. 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.