What Is Endpoint Detection and Response (EDR)

If your business security still relies mainly on traditional antivirus, you are not alone. But the threat landscape has changed. Ransomware, credential theft, and remote access attacks often slip past legacy tools because attackers do not always use known malware signatures.

That is where endpoint detection and response, commonly called EDR, comes in.

This guide explains what EDR is, how it works, how it differs from antivirus, and how Phoenix businesses can decide if they need it.

What is EDR?

EDR is a security tool that monitors endpoint activity, laptops, desktops, and servers, looking for suspicious behaviour, not just known malware.

Instead of only scanning files, EDR watches what is happening:

• Processes launching and chaining together

• Unexpected PowerShell or script activity

• Strange credential usage

• Mass file encryption behaviour

• Connections to known malicious domains

• Privilege escalation attempts

When it detects high risk activity, it can alert, quarantine, or isolate a device to prevent spread.

EDR vs antivirus, what is the difference?

Antivirus primarily tries to block known threats based on signatures and basic heuristics. It is still useful, but it is not designed for the speed and tactics of modern attacks.

EDR focuses on:

• Behaviour based detection

• Visibility into what happened, and how

• Faster response actions

• Investigation, timelines, and remediation guidance

Think of antivirus as a lock, and EDR as a camera plus alarm system that also helps you respond.

Why EDR matters for ransomware

Ransomware does not always start as “ransomware”. It often begins as:

• A stolen Microsoft 365 password

• A remote session on a compromised device

• An attacker using built in tools to move around quietly

By the time encryption starts, the attacker may already have access to multiple systems.

EDR helps by:

• Detecting suspicious steps earlier in the attack chain

• Alerting on lateral movement and privilege escalation

• Isolating a device before encryption spreads

• Providing evidence for recovery and insurance

What EDR typically detects that antivirus can miss

Here are common behaviours EDR is designed to spot:

Credential theft attempts

Tools that dump passwords or tokens from memory.

Suspicious scripting

PowerShell, cmd, or other scripts used to download payloads or disable security.

Lateral movement

Unusual remote connections between devices and servers.

Unusual admin activity

New admin accounts, unexpected privilege changes, or remote management abuse.

Mass changes to files

A spike in encryption like behaviour, renaming, and deletion.

Do small businesses need EDR?

Many people assume EDR is only for large companies. In reality, small and mid sized businesses are often targeted because they have fewer defences.

You should strongly consider EDR if:

• You store sensitive data, client info, or PHI

• You rely on Microsoft 365 for email and files

• Remote work is common

• You have compliance requirements or cyber insurance

• Downtime would be costly

• You do not have internal security monitoring

For law firms, healthcare clinics, financial services, and professional services, EDR is often a baseline expectation now.

EDR alone is not enough, monitoring matters

EDR generates alerts. But alerts only help if someone is watching and responding. Many organisations have EDR installed but no one actively manages it.

That is why many teams combine EDR with:

• 24/7 monitoring through a SOC

• Clear incident response steps

• Regular review of detections and trends

• Patch management and identity hardening

Security improves most when tools and processes work together.

What to look for when choosing an EDR solution

Not all EDR implementations are equal. Look for:

• Behaviour based detection and isolation capability

• Simple reporting that you can understand

• Integration with Microsoft 365 and identity

• Clear escalation and response support

• Ongoing tuning, not set it and forget it

• Coverage for servers, not just laptops

A simple EDR readiness checklist

If you want to validate your setup, check these:

• EDR installed on every endpoint, including servers

• Alerts go to a monitored inbox or ticketing system

• A response plan exists, who does what

• Devices are centrally managed and patched

• MFA is enforced for Microsoft 365 and admin access

• Backups are tested and protected from encryption