Legacy AV Removal · EDR Deployment · MITRE Validated

Endpoint Security Migration
From Antivirus to EDR

Replace legacy antivirus with modern EDR — CrowdStrike Falcon or FortiEDR. Ogma handles agent deployment, policy design, exclusion tuning, legacy AV removal, and post-migration attack simulation to validate detection coverage.

Why EDR Matters

Legacy Antivirus Is Not Enough

Signature-based antivirus was effective when malware was distributed as executable files with known hashes. That era ended years ago. Modern attackers use fileless techniques — PowerShell scripts, WMI persistence, registry run keys, DLL side-loading, and process injection — that leave no files for AV to scan.

Ransomware groups like LockBit, BlackCat, and Cl0p use living-off-the-land binaries (LOLBins) — legitimate system tools like PsExec, certutil, and wmic — to move laterally and deploy payloads. Legacy AV sees these as trusted system processes and does nothing.

EDR changes the paradigm. Instead of matching signatures, it monitors endpoint behaviour — process trees, API calls, network connections, registry modifications — and uses AI to detect malicious patterns in real-time. When a threat is detected, EDR can isolate the endpoint, kill the process, and quarantine artifacts automatically.

95-99%
ATT&CK Detection Rate (EDR)
<40%
Detection Rate (Legacy AV)
<1%
CPU Overhead (Falcon)
0
Protection Gaps

Legacy AV vs Modern EDR — Compared

Understanding the fundamental capability gap between signature-based AV and behavioural EDR.

Capability Legacy Antivirus Modern EDR (CrowdStrike)
Detection Method Signature matching, basic heuristics Behavioural AI, ML models, IOA patterns
Fileless Attacks Cannot detect (no file to scan) Monitors process behaviour, API calls, memory
Ransomware Prevention Only known variants (signature match) Behavioural detection of encryption patterns
Incident Response Quarantine file only Network isolation, process kill, remote shell, forensics
Visibility Scan results and quarantine logs Full process tree, network connections, file changes
Threat Hunting Not supported Query endpoint telemetry across entire fleet
Update Mechanism Daily signature updates (DAT files) Cloud-native, real-time threat intelligence
Performance Impact Heavy during full scans (high CPU, disk I/O) Lightweight agent, no scheduled scans needed

Migration Methodology

1

Endpoint Discovery

Inventory all endpoints — Windows workstations, servers, macOS devices, Linux hosts. Identify current AV product, version, and management server. Map OS versions, patch levels, and hardware specs. Identify endpoints not covered by any protection (shadow IT, unmanaged devices).

2

Policy & Exclusion Design

Design prevention policies per endpoint group (workstations, servers, VDI, OT). Configure detection sensitivity, automated response actions, and network containment thresholds. Build exclusion lists for business-critical applications, development tools, and backup agents. Map existing AV exclusions to EDR equivalents.

3

Pilot Deployment (Detect-Only)

Deploy EDR agent on pilot group (IT team + representative sample from each department) in detection-only mode. Both AV and EDR run simultaneously. Monitor for false positives, performance issues, and application compatibility for 2-3 weeks. Tune exclusions and policies based on findings.

4

Production Rollout (Phased)

Roll out EDR agent to all endpoints in waves — department by department or site by site. Use Intune, SCCM, or GPO for automated deployment. Enable prevention mode on pilot endpoints once detection-only period validates accuracy. Each wave gets 3-5 days of monitoring before the next wave begins.

5

Legacy AV Removal

Once EDR is in prevention mode and validated on all endpoints, remove legacy AV using vendor-provided cleanup tools (Norton Removal Tool, McAfee MCPR, Kaspersky Removal Tool, etc.). Verify complete removal — leftover drivers and services can cause conflicts. Reclaim system resources freed by AV removal.

6

Validation & Attack Simulation

Run Breach & Attack Simulation (BAS) to validate detection coverage against MITRE ATT&CK framework. Test credential dumping, lateral movement, ransomware simulation, C2 communication, and data exfiltration techniques. Address any detection gaps with policy tuning. Provide final coverage report and handover documentation.

Agent Deployment Methods

Microsoft Intune

Cloud-native deployment for Entra ID-joined and hybrid-joined devices. Push the EDR MSI/EXE as a Win32 app or line-of-business app. Detection rules verify successful installation. Ideal for distributed and remote workforces.

SCCM / MECM

Enterprise on-premises deployment for large environments. Create application or package deployments with required assignments. Schedule deployment windows to avoid business-hours disruption. Compliance reports track installation status across all collections.

Group Policy (GPO)

Domain-joined Windows endpoints via startup scripts or scheduled tasks. No additional infrastructure required beyond existing Active Directory. WMI filters target specific OS versions or hardware configurations. Deployment logs centralised via Event Forwarding.

macOS (Jamf / Munki)

Deploy CrowdStrike Falcon as a macOS PKG with required system extensions and Full Disk Access permissions pre-approved via MDM profiles. PPPC (Privacy Preferences Policy Control) profiles ensure silent installation without user prompts.

Linux (Ansible / Puppet)

Configuration management tools deploy and configure the Falcon sensor on RHEL, CentOS, Ubuntu, Debian, and Amazon Linux. Ansible playbooks handle installation, CID registration, and proxy configuration. Kernel compatibility verified pre-deployment.

Manual / Standalone

For standalone machines, air-gapped systems, or OT environments without centralised management. Pre-built installation packages with embedded CID and proxy settings. USB-based deployment for offline systems. Kiosk and VDI golden image integration.

CrowdStrike Falcon — Module Breakdown

Single lightweight agent, multiple security modules activated via cloud console.

Falcon Prevent (NGAV)

Next-gen antivirus using machine learning and Indicators of Attack (IOA) to stop known and unknown malware, ransomware, and fileless attacks. Replaces traditional AV with no signature updates required.

Falcon Insight (EDR)

Full endpoint detection and response with continuous recording of endpoint activity. Process trees, file modifications, network connections, and registry changes are stored for investigation. Real-Time Response enables remote remediation.

Falcon OverWatch (Threat Hunting)

CrowdStrike's elite threat hunters monitor your environment 24/7 for stealthy adversary activity that automated detection might miss. They proactively hunt for nation-state actors, insider threats, and sophisticated intrusions.

Falcon Identity Protection

Detects identity-based attacks — credential theft, lateral movement via compromised accounts, and Active Directory reconnaissance. Integrates with AD to enforce risk-based conditional access without requiring MFA changes.

Legacy AV Removal Challenges We Solve

Tamper Protection

Enterprise AV products have tamper protection that prevents uninstallation. We use vendor-specific admin passwords, management console bulk uninstall commands, and dedicated removal tools.

Residual Drivers

Leftover kernel drivers and services from incomplete uninstallation cause conflicts with new EDR agents. We verify clean removal at the driver level and run vendor cleanup tools.

Mixed Environments

Multiple AV products from past acquisitions or inconsistent policy enforcement. We handle heterogeneous removal — Norton, McAfee, Kaspersky, Trend Micro, Sophos — in a single project.

Server Workloads

Servers require careful exclusion design to avoid impacting SQL Server, Exchange, IIS, or application performance. We validate with load testing before enabling prevention mode on production servers.

Post-Migration MITRE ATT&CK Validation

We do not just deploy EDR — we prove it works using real-world attack simulations.

Techniques We Simulate

  • Initial Access — phishing payload execution, macro-enabled documents
  • Execution — PowerShell, WMI, MSHTA, Rundll32, Regsvr32
  • Persistence — registry run keys, scheduled tasks, startup folder
  • Privilege Escalation — UAC bypass, token manipulation
  • Credential Access — LSASS dump, SAM dump, Kerberoasting
  • Lateral Movement — PsExec, WMI remote, RDP, SMB
  • Collection & Exfiltration — data staging, DNS exfiltration

What You Get

  • MITRE ATT&CK coverage heatmap for your environment
  • Per-technique detection/prevention status report
  • False positive analysis and exclusion recommendations
  • Gap analysis with remediation steps
  • Comparison with MITRE evaluation results for your EDR
  • Executive summary for board/audit reporting
  • Quarterly re-testing schedule (optional)

Frequently Asked Questions

Traditional antivirus relies on signature-based detection — it can only detect known malware that has been previously catalogued. Modern threats use fileless attacks, living-off-the-land binaries (LOLBins), memory-only payloads, and polymorphic malware that signatures cannot catch. EDR provides behavioural analysis, AI-based detection, real-time response, and full endpoint telemetry. In MITRE ATT&CK evaluations, leading EDR platforms detect 95-99% of adversary techniques while legacy AV catches less than 40%.

We run both solutions in parallel during a controlled coexistence period (typically 2-4 weeks). The new EDR agent is deployed in detection-only (monitor) mode first to build a baseline and identify false positives. The old AV remains active for protection. Once we validate that EDR detection is accurate and exclusions are tuned, we switch EDR to prevention mode and uninstall the old AV. This ensures zero gaps in protection.

We support all major deployment methods: Microsoft Intune (for cloud-managed devices), SCCM/MECM (for on-premises managed devices), Group Policy (GPO) for domain-joined Windows endpoints, manual installation packages for standalone machines, and platform-native tools for macOS (Jamf, Munki) and Linux (Ansible, Puppet, Chef). We select the best method based on your existing management infrastructure.

Agent deployment itself is fast — we can push to 500-1000 endpoints per day with proper infrastructure. The overall project timeline is typically 4-8 weeks: 1 week for assessment and policy design, 1-2 weeks for pilot deployment and tuning, 2-4 weeks for phased production rollout, and 1 week for validation and handover. Larger environments (5000+ endpoints) may take 8-12 weeks.

Modern EDR agents like CrowdStrike Falcon are lightweight by design — typically consuming less than 1% CPU and 50-80 MB RAM during normal operation. During the pilot phase, we benchmark CPU, memory, disk I/O, and boot times before and after agent installation. If we find specific applications impacted, we create targeted exclusions. The performance difference versus legacy AV is usually neutral or better since EDR agents do not perform full-disk scans.

Exclusions are critical for preventing false positives and performance issues with business applications. We start with vendor-recommended exclusions (Microsoft, CrowdStrike, application vendors) and add environment-specific exclusions identified during the pilot phase. All exclusions are documented with justifications and reviewed quarterly. We use CrowdStrike's Machine Learning exclusion policies and IOA exclusions to minimise broad path-based exclusions that could create security gaps.

Yes. After deployment, we run Breach & Attack Simulation (BAS) using Ogma's simulation platform to test detection of MITRE ATT&CK techniques — credential dumping, lateral movement, privilege escalation, data exfiltration, and more. We verify that each technique generates an alert in your EDR console. Any detection gaps are addressed with policy adjustments or additional CrowdStrike modules (Identity Protection, Cloud Security).

We offer tiered endpoint security solutions. CrowdStrike Falcon Go (NGAV + device control) is the entry point at a competitive per-endpoint price. For budget-conscious organisations, we also deploy FortiClient with FortiEDR which integrates with existing Fortinet Security Fabric deployments at a lower per-endpoint cost. We help you choose based on threat landscape, compliance requirements, and budget.

Ready to Upgrade to Modern Endpoint Security?

Get a free endpoint security assessment. We will audit your current AV coverage, identify gaps, and recommend the right EDR solution with a phased migration plan.

CrowdStrike Solutions