Elastic Security Informational Severity

[WildDogOne]

Elastic Security does now know the severity Informational.
It only understands Low, Medium, High, Critical.
Since Sigma does allow Informational (as it is designed to) there will be the possibility of getting Informational Severity (Level in Sigma)

I propose to add code to bump Severity of Informational to Low, but for example setting the riskScore to 0.

for Example in the finalize_query_siem_rule_ndjson and finalize_query_siem_rule functions
https://github.com/SigmaHQ/pySigma-backend-elasticsearch/blob/main/sigma/backends/elasticsearch/elasticsearch_eql.py#L379
https://github.com/SigmaHQ/pySigma-backend-elasticsearch/blob/main/sigma/backends/elasticsearch/elasticsearch_eql.py#L450

"riskScore": (
    0 if rule.level is not None and str(rule.level.name).lower() == "informational"
    else self.severity_risk_mapping[rule.level.name] if rule.level is not None
    else 21
),
"riskScoreMapping": [],
"severity": (
    "low" if rule.level is None or str(rule.level.name).lower() == "informational" else str(rule.level.name).lower()
),