[Rule Tuning] 3rd Party EDR Compatibility - 6

[w0rk3r]

Issues

• https://github.com/elastic/ia-trade-team/issues/406
• https://github.com/elastic/ia-trade-team/issues/407

Summary

Adjusts to rules to introduce or improve compatibility and documentation with 3rd party data such as Sysmon, MDE, and S1.

EDR field compatibility matrix: https://docs.google.com/spreadsheets/d/1ZaRmSXIVYLO9AGXeZge3u0W938aGxbfd6Vha52Rs1_I/edit?usp=sharing

Blocker

To use SentinelOne cloud funnel data right now, we would need to min_stack the rules to 8.13, so we are going to hold off on merging these until 8.16 is released and support for 8.12 is dropped. The updated_date is set to the 8.16 public release date.

[protectionsmachine]

Rule: Tuning - Guidelines

These guidelines serve as a reminder set of considerations when tuning an existing rule.

Documentation and Context

• Detailed description of the suggested changes.
• Provide example JSON data or screenshots.
• Provide evidence of reducing benign events mistakenly identified as threats (False Positives).
• Provide evidence of enhancing detection of true threats that were previously missed (False Negatives).
• Provide evidence of optimizing resource consumption and execution time of detection rules (Performance).
• Provide evidence of specific environment factors influencing customized rule tuning (Contextual Tuning).
• Provide evidence of improvements made by modifying sensitivity by changing alert triggering thresholds (Threshold Adjustments).
• Provide evidence of refining rules to better detect deviations from typical behavior (Behavioral Tuning).
• Provide evidence of improvements of adjusting rules based on time-based patterns (Temporal Tuning).
• Provide reasoning of adjusting priority or severity levels of alerts (Severity Tuning).
• Provide evidence of improving quality integrity of our data used by detection rules (Data Quality).
• Ensure the tuning includes necessary updates to the release documentation and versioning.

Rule Metadata Checks

• updated_date matches the date of tuning PR merged.
• min_stack_version should support the widest stack versions.
• name and description should be descriptive and not include typos.
• query should be inclusive, not overly exclusive. Review to ensure the original intent of the rule is maintained.

Testing and Validation

• Validate that the tuned rule's performance is satisfactory and does not negatively impact the stack.
• Ensure that the tuned rule has a low false positive rate.

[w0rk3r]

Merging those with min_stack to unblock other 3rd party EDR work.