EDR on endpoints: why traditional antivirus is not enough in PR

Brian Krebs frequently documents on Krebs on Security how ransomware groups evade traditional antivirus signatures using fresh variants and living-off-the-land techniques. In Puerto Rico we see the same pattern: distributors in Bayamón and law firms in Hato Rey running "enterprise" suites that block known malware but miss lateral movement when an accountant opens a fake tax authority attachment.

EDR — Endpoint Detection and Response — is not antivirus with new marketing. It is continuous telemetry on processes, network connections, registry changes, and automated or assisted response. CISA recommends EDR capabilities as baseline for organizations with sensitive data; for a 40-user SMB, Microsoft Defender for Business or CrowdStrike Falcon Go are reasonable entry points without six-figure contracts.

Implementation matters as much as licensing. Deploy on all laptops — including approved BYOD — integrate with identity (M365 or Google), and document exclusion rules. The typical PR mistake is installing the agent and never reviewing alerts because "nobody watches them." Without weekly triage, EDR is an expensive log of incidents that already happened.

We recommend starting with three playbooks: active ransomware (isolate host, preserve memory, escalate), stolen credentials (forced reset, cloud session review), and suspicious admin tooling (PsExec, Mimikatz patterns). A regional MSSP or IR retainer can cover off-hours hunting if your internal IT is two people.

Puerto Rico shares threats with the mainland US but on Caribbean SMB budgets. Well-operated EDR closes the gap between "we have antivirus" and "we can respond before QuickBooks servers get encrypted." That is what enterprise customers now ask when renewing contracts with local vendors.