Stop Asking If EDR Kills Antivirus — You Need Both, and Here's Why

I'm going to say something that might get me flamed by the EDR-only crowd: if you rip out your antivirus and run only EDR, you're making a mistake. I know, I know — the marketing says EDR is the future and AV is a dinosaur. But the data doesn't back that up. The CrowdStrike 2026 Global Threat Report shows 82% of detections in 2025 were malware-free, which sounds like a slam dunk for EDR. But that also means 18% of detections still involved traditional malware. That's not nothing. And while EDR catches the clever stuff, antivirus still has a job: filtering out the commodity noise before it becomes a problem. So let's bust some myths and answer the questions I actually get from readers.

Isn't EDR Just a Better Antivirus?

No, and this is the most common misconception. Antivirus is a prevention tool that matches files against known signatures to block and remove known malware (CISA). EDR is a detection and response tool that continuously monitors endpoint activity, using behavioral analysis and machine learning to catch both known and unknown threats — including fileless malware and zero-days (CISA). They're fundamentally different layers. AV is a guard at the door; EDR is a security camera that follows you around the building and can tackle you if you act suspicious. One doesn't replace the other.

If EDR Catches Zero-Days, Why Bother with AV at All?

Because AV is cheap insurance against the mundane. EDR is designed to catch sophisticated attacks, but it's noisy — it generates alerts for things that look odd, and if it's constantly pinged by commodity malware, you get alert fatigue. Antivirus filters out the known stuff so EDR can focus on the real threats (CISA). Think of it this way: you wouldn't hire a SWAT team to handle a shoplifter. You have a security guard for that, and SWAT for the hostage situation. Running AV alongside EDR is the security guard and SWAT combined.

But My EDR Vendor Says It Replaces AV. Are They Lying?

They're not lying, but they're selling you a product. Some EDR products do include AV-like capabilities, but the definition of 'antivirus' has blurred. What I care about is the function: signature-based blocking of known malware. If your EDR doesn't do that, you need separate AV. The CISA guidance is clear: most organizations are advised to run antivirus alongside EDR, letting EDR focus on sophisticated threats rather than commodity malware noise (CISA). So unless you're a tiny shop with a single security tool, keep both.

What About XDR? Is That the New EDR?

XDR is an extension, not a replacement. XDR correlates telemetry across endpoints, identity, email, and cloud, extending detection beyond the endpoint (Cisco). That's great if you have a mature security stack. But if you don't have solid EDR first, XDR is just a fancy dashboard over missing data. Start with EDR, then consider XDR when you have the basics covered.

How Do EDR and Zero Trust Fit Together?

Zero Trust is a framework, not a tool. It's 'never trust, always verify', with explicit verification and least privilege (Cisco). EDR is reactive and detective; Zero Trust is proactive and preventive (Cisco). They complement each other. For example, NIST SP 800-207 says to grant access on a per-session basis and only the minimum privileges needed (NIST SP 800-207). EDR can't do that. But Zero Trust can't detect a fileless attack that's already inside. You need both.

So What Should I Actually Deploy?

Here's my recommendation: deploy both AV and EDR, integrate them, and use a framework like MITRE ATT&CK to map your defenses. MITRE ATT&CK is a knowledge base of real-world adversary tactics and techniques, and it's free (MITRE ATT&CK). Use it to understand what you're defending against. Also, don't forget backups and patching — CISA's StopRansomware guidance says backing up is your best bet for recovery, and patching is critical (CISA StopRansomware). And if you're wondering which EDR to pick, the leading platforms include CrowdStrike Falcon, Microsoft Defender for Endpoint, SentinelOne Singularity, Palo Alto Cortex XDR, and Trend Micro Vision One (CISA).

Quick tip: If you're on a budget, start with a free AV and a trial of an EDR, but don't skip either layer. And don't forget to test your backups — offline, encrypted, and regularly (CISA StopRansomware).

Sources

• CISA - https://www.cisa.gov/stopransomware
• CrowdStrike 2026 Global Threat Report - https://www.crowdstrike.com/en-us/global-threat-report/
• Cisco - https://www.cisco.com/site/us/en/learn/topics/security/what-is-endpoint-security.html
• NIST SP 800-207 - https://doi.org/10.6028/NIST.SP.800-207
• MITRE ATT&CK - https://attack.mitre.org/