A clear, beginner-friendly guide to how Wazuh decoders and rules work together — what fields are, where they come from, when you need a decoder, and how logs become alerts.
Tags: Wazuh · OSSEC · SIEM · Blue Team · Detection Engineering
Level: Beginner → Intermediate | Read time: 15 min
If you’ve ever looked at a Wazuh rule file and asked yourself:
- "Where does this field come from — the rule, the decoder, or the log itself?"
- "Do I even need a decoder for this rule to work?"
- "Why does my
<field> rule never fire even though the string is clearly in the log?"
…you are not alone. These are the exact questions most people hit when they start writing Wazuh rules. This post answers all of them, step by step, with diagrams at every stage.
Continue reading “Wazuh Decoders & Rules: The Missing Mental Model” →