RedLegg MDR with Managed SIEM is a managed detection and response service that combines SIEM management with threat detection and response capabilities. The service provides data aggregation and correlation from customer log sources into a centralized location to identify malicious activity through pattern analysis. The platform includes onboarding guidance using a four-tier logging prioritization methodology to monitor high-value logs. Custom detection logic is developed by the Cyber Threat Intelligence team and Platform Operations Engineers based on customer-specific use cases and business threats. The service features automated and analyst-driven response actions, including endpoint isolation and user session revocation based on EDR detections. Response actions are customizable to customer risk tolerance and integrate with SOAR platforms to correlate EDR and SIEM data. Continuous tuning is performed by the Cyberfusion team to maintain detection effectiveness and reduce false positives. The service includes Detection Logic Lifecycle management and threat modeling to optimize SIEM performance. RedLegg offers two deployment models: Co-Managed SIEM where customers own hosts, software, and licenses while RedLegg manages the deployment, and Hosted SIEM where RedLegg provides infrastructure. The service supports both new SIEM deployments and existing customer-owned SIEM instances without requiring replacement.