Mark-of-the-Web Removal by an Unusual Process

Last updated 3 days ago on 2026-07-30

Created 3 days ago on 2026-07-30

About

Identifies an unusual process deleting the Zone.Identifier alternate data stream from an executable or Windows Installer package. Attackers can remove this stream to bypass Mark-of-the-Web protections.

Tags

Domain: EndpointOS: WindowsUse Case: Threat DetectionTactic: Defense EvasionData Source: Elastic DefendLanguage: eql

Severity

low

Risk Score

MITRE ATT&CK™

Defense Evasion (TA0005)(external, opens in a new tab or window)

↳ Subvert Trust Controls (T1553)(external, opens in a new tab or window)

False Positive Examples

Browsers, download utilities, and security tools may remove Mark-of-the-Web during legitimate file handling.Administrative scripts and software deployment tools may intentionally unblock trusted executables or installers.

License

Elastic License v2(external, opens in a new tab or window)

Definition

Rule Type: Event Correlation Rule
Integration Pack: Prebuilt Security Detection Rules
Index Patterns: logs-endpoint.events.file-*
Related Integrations: endpoint(external, opens in a new tab or window)
Query

✄𐘗text code block:
✄𐘗file where host.os.type == "windows" and event.type == "deletion" and
  file.path : (
    "*.exe:Zone.Identifier",
    "*.exe:Zone.Identifier:$DATA",
    "*.msi:Zone.Identifier",
    "*.msi:Zone.Identifier:$DATA"
  ) and

  /* Explorer may remove MOTW after SmartScreen */
  not (
    process.executable : "?:\\Windows\\explorer.exe" and
    process.code_signature.trusted == true and
    process.code_signature.subject_name : "Microsoft Windows"
  )

Install detection rules in Elastic Security

Detect Mark-of-the-Web Removal by an Unusual Process in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(external, opens in a new tab or window).