Security Comparison — Melbourne
Antivirus vs Managed Detection and Response (MDR)
Antivirus was designed for a different threat landscape. Modern ransomware, identity attacks, and fileless techniques routinely bypass it. This comparison explains what MDR does that antivirus cannot — and why it matters for Melbourne businesses with compliance obligations.
Antivirus uses signature-based detection to block known malware. Managed Detection and Response (MDR) combines security technology with human analysts who continuously monitor, hunt, and respond to threats — including ransomware precursors, identity attacks, and novel techniques antivirus cannot detect. For Melbourne businesses with ACSC Essential Eight obligations or client data, MDR provides the coverage and response capability antivirus cannot.
Side-by-side comparison
| Category | Traditional Antivirus | MDR (Prexiam) |
|---|---|---|
| Threat detection | Signature-based. Detects known malware. Misses novel ransomware variants and fileless attacks. | 24/7 behavioural detection. Identifies anomalous activity — including fileless, living-off-the-land, and identity attacks. |
| Human response | None. Antivirus quarantines files automatically. No investigation or containment guidance. | Security analysts investigate alerts, confirm threats, and provide guided containment actions. |
| Ransomware protection | Limited. Modern ransomware disables antivirus before encrypting. No backup or recovery integration. | MDR detects pre-ransomware behaviour (credential theft, lateral movement) and integrates with immutable backup recovery. |
| Essential Eight alignment | Partially addresses "malicious code prevention." Does not address 7 of the 8 controls. | MDR directly supports Essential Eight ML1–ML2 controls including patching, application hardening, and admin privilege restriction. |
| Identity attack detection | Does not monitor identity events, MFA bypass attempts, or privileged access misuse. | Monitors Microsoft Entra ID sign-in risk, MFA bypass attempts, and privileged access anomalies. |
| Incident response | No incident response. You discover the breach from operational impact, not security telemetry. | 30-minute virtual incident bridge (SLA-backed target). Containment, evidence preservation, and recovery path. |
| Monthly cost | $5–$15 per endpoint per month. Low upfront, but no coverage. | Higher per-endpoint cost. Includes monitoring, hunting, response, and reporting. Prevents incidents that cost far more. |
| Best for | Home users and micro-businesses with minimal data risk and no compliance obligations. | Melbourne businesses with client data, compliance obligations (APP, Essential Eight), or ransomware recovery concerns. |
Why antivirus fails against modern threats
Ransomware disables antivirus first
Modern ransomware operators disable or uninstall endpoint security before executing the encryption payload. By the time antivirus would trigger, it's already been neutralised. MDR detects the precursor activity — credential theft, privilege escalation — before the payload runs.
Fileless and living-off-the-land attacks
Attackers increasingly use legitimate tools (PowerShell, WMI, PsExec) to move laterally and execute payloads without dropping files that antivirus can scan. MDR behavioural detection identifies anomalous use of these tools regardless of whether a malicious file exists.
Identity attacks bypass endpoint security
Microsoft Entra ID credential compromise, MFA bypass, and token theft happen in the identity layer — not at the endpoint. Antivirus has no visibility into identity events. MDR monitors sign-in risk, MFA anomalies, and privileged access misuse in real time.
Frequently asked questions
What is the difference between antivirus and MDR?
Antivirus uses signature-based detection to block known malware. Managed Detection and Response (MDR) combines security technology with human expertise to continuously monitor, hunt, and respond to threats — including novel ransomware, identity attacks, and fileless techniques that antivirus cannot detect.
Does antivirus protect against ransomware?
Partially. Modern ransomware variants are designed to evade signature-based antivirus by disabling it before encrypting files, using fileless techniques, or exploiting trusted applications (living off the land). MDR detects pre-ransomware behaviours — credential theft, lateral movement, privilege escalation — before encryption begins.
What does ACSC say about antivirus vs MDR for Essential Eight?
The ACSC Essential Eight includes "malicious code prevention" as one of eight controls — which antivirus partially addresses. However, Essential Eight ML2 and ML3 require patch automation, application control, admin privilege restriction, and MFA — none of which antivirus covers. MDR supports a broader Essential Eight uplift program.
What is 24/7 MDR and what does it include?
24/7 Managed Detection and Response combines security technology with human security analysts who continuously monitor your environment, hunt for threats, investigate alerts, and provide guided containment and response. It should include monitoring, threat hunting, alert investigation, containment guidance, and incident reporting — not just automated alerting.
How does MDR help with the ACSC Essential Eight in Melbourne?
MDR directly supports multiple Essential Eight controls: it monitors for patching gaps (patch applications), detects application control violations, identifies admin privilege misuse (restrict admin privileges), and alerts on MFA bypass attempts. Combined with Prexiam's continuous posture enforcement, MDR keeps Essential Eight maturity at the target level operationally.
Want to know if your current security stack covers modern threats?
Book a free IT assessment. We'll review your current security posture and map gaps against ACSC Essential Eight controls.