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Vol. 1 · Ed. 2026
CyberGlossary
Entry № 1041

Sigma Rule

What is Sigma Rule?

Sigma RuleA vendor-neutral, YAML-based detection signature for log events that can be converted into queries for SIEM, EDR, or XDR back-ends.


Sigma is an open detection-engineering format created by Florian Roth and Thomas Patzke that lets analysts describe log-based detections once and translate them into many SIEM dialects (Splunk SPL, Elastic ESQL, Microsoft Sentinel KQL, Chronicle, etc.) using converters such as pySigma or Sigma CLI. A Sigma rule combines metadata (id, level, MITRE ATT&CK mapping), a logsource (product, service, category) and a detection block with selectors and a condition. The Sigma HQ repository hosts thousands of community rules covering Windows Event Logs, Sysmon, Linux audit, AWS CloudTrail, Okta, and more, supporting portable, sharable detection content.

Examples

  1. 01

    A Sigma rule detecting suspicious child processes of winword.exe to flag macro-driven malware.

  2. 02

    Converting a Sigma rule with pySigma into Microsoft Sentinel KQL for an analytics rule deployment.

Frequently asked questions

What is Sigma Rule?

A vendor-neutral, YAML-based detection signature for log events that can be converted into queries for SIEM, EDR, or XDR back-ends. It belongs to the Defense & Operations category of cybersecurity.

What does Sigma Rule mean?

A vendor-neutral, YAML-based detection signature for log events that can be converted into queries for SIEM, EDR, or XDR back-ends.

How does Sigma Rule work?

Sigma is an open detection-engineering format created by Florian Roth and Thomas Patzke that lets analysts describe log-based detections once and translate them into many SIEM dialects (Splunk SPL, Elastic ESQL, Microsoft Sentinel KQL, Chronicle, etc.) using converters such as pySigma or Sigma CLI. A Sigma rule combines metadata (id, level, MITRE ATT&CK mapping), a logsource (product, service, category) and a detection block with selectors and a condition. The Sigma HQ repository hosts thousands of community rules covering Windows Event Logs, Sysmon, Linux audit, AWS CloudTrail, Okta, and more, supporting portable, sharable detection content.

How do you defend against Sigma Rule?

Defences for Sigma Rule typically combine technical controls and operational practices, as detailed in the full definition above.

What are other names for Sigma Rule?

Common alternative names include: Sigma signature, Sigma format.

Related terms

See also