OT/ICS Security Audit
85% of industrial companies have critical OT vulnerabilities they don't know about. We'll identify vulnerabilities, configuration errors, segmentation weaknesses. You get prioritized remediation plan without production impact.
Describe your scope — your account manager will reply within 24 hours.
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What is an OT/ICS Security Audit?
An OT/ICS security audit is a comprehensive, non-invasive assessment of industrial control systems — including SCADA, PLC, HMI, and DCS — that identifies vulnerabilities, configuration errors, and segmentation weaknesses without stopping production. nFlo conducts passive audits using methods that never interfere with operational systems, delivering a prioritized remediation plan fully compliant with NIS2 and IEC 62443 requirements.
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Discuss OT/ICS Security Audit with your dedicated account manager.
You don't know what doesn't work until it's too late
Comprehensive OT security audit
Network Assessment
Segmentation, firewall rules, communication
Configuration Review
SCADA, PLC, HMI - hardening and patching
Vulnerability Scan
Passive security vulnerability scanning
Cyberattack Detected by Customer, Not IT
Manufacturing company with SCADA systems managing 6 production lines. Production anomalies - defective products for 2 weeks. It turned out: modified parameters in PLC by malicious software. IT didn’t know about the attack for 14 days. Loss: €82K in defective products and halted production.
Without regular OT audits:
- You don’t know about security vulnerabilities in industrial systems
- Attacks detected too late or not at all
- Outdated firmware versions with critical CVEs
- Lack of segmentation allows attack spread
Audit That Doesn’t Stop Production
We conduct comprehensive OT/ICS security audit using non-invasive methods. We identify vulnerabilities, configuration errors, architecture weaknesses - without affecting production system operation.
What you get:
- Passive OT network mapping and device inventory
- IT/OT segmentation and communication flow analysis
- SCADA, HMI, PLC, DCS configuration review for security
- Passive OT component vulnerability scanning
- Access management and patching assessment
- OT backup and disaster recovery verification
- Report with prioritized remediation plan (risk-based)
- Results presentation for management and technical team
Who Is It For?
This service is for you if:
- You run production on OT/ICS systems and haven’t done security audit
- You need to meet NIS2 requirements for critical infrastructure
- Integrators or customers require OT security audit
- You suspect security issues but aren’t sure
- You’re planning OT security investments and need prioritization
OT/ICS Audit Scope
What Do We Check?
Comprehensive OT environment security assessment:
Network Security
- IT/OT segmentation (Purdue Model)
- Firewall rules between zones
- VLANs and access control lists
- Remote access (VPN, vendor access)
Device Security
- SCADA servers - hardening, patching
- HMI stations - OS security, access control
- PLC/DCS - firmware versions, default passwords
- Engineering workstations - antivirus, patching
Access Management
- Account management (default accounts, shared passwords)
- Multi-factor authentication
- Privilege management
- Session logging and monitoring
Configuration Security
- Communication protocols (plain text vs encrypted)
- Backup procedures
- Change management for OT changes
- Logging and monitoring
Vulnerability Assessment
- Passive CVE scanning for OT components
- Firmware/software version analysis
- Known vulnerabilities for used protocols
- Comparison with CISA Known Exploited Vulnerabilities
What We Look For
Common OT Vulnerabilities
Network Level:
- Flat network - no IT/OT segmentation
- Direct internet access from OT network
- Uncontrolled vendor remote access
- Missing firewall between zones
System Level:
- Windows XP/7 on HMI stations (EOL)
- Unpatched SCADA software
- Default passwords on PLCs
- Unnecessary services enabled
Protocol Level:
- Modbus without authentication
- OPC Classic without encryption
- Telnet/FTP instead of SSH/SFTP
- Clear text protocols on critical segments
Access Level:
- Shared accounts for operators
- No MFA for remote access
- Excessive privileges
- No audit logging
Audit vs Pentest
| Aspect | Audit | Pentest |
|---|---|---|
| Method | Passive review | Active testing |
| Risk | None | Minimal (controlled) |
| Focus | Configuration, compliance | Exploitability |
| Output | Gap analysis | Exploit proof |
| Time | 2-4 weeks | 5-15 business days |
| When | Annual, first assessment | After hardening |
We recommend: Audit first, then pentest to verify controls.
Related Glossary Terms
Learn more about key concepts related to this service:
How we work
Our proven service delivery process.
Kick-off
Scope, access, audit schedule
Discovery
Passive OT network and device mapping
Assessment
Configuration, vulnerability, segmentation analysis
Report
Detailed report with risk prioritization
Presentation
Results discussion and remediation plan
Benefits for your business
What you gain by choosing this service.
Know Your Weak Points
Specific threat list with priorities
Remediation Plan
Know what to do to be secure
NIS2 and IEC 62443 Compliance
Meet regulatory requirements
No Production Impact
Audit doesn't stop production lines
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Read more →Frequently Asked Questions
Common questions about OT/ICS Security Audit.
How much does OT/ICS security audit cost?
Small plant (1-2 lines, basic SCADA): €7,000-11,500. Medium (multiple production areas): €14,000-23,000. Large industrial complex: €27,500-46,000. Includes all analysis, report, and management presentation.
Does OT audit require production downtime?
No. We use exclusively passive methods - configuration analysis, traffic monitoring, documentation review. We don't perform active scans that could disrupt PLC or SCADA operation.
How long does OT audit take?
An audit takes 2-4 weeks depending on plant size. For a medium factory it is about 3 weeks: one week discovery and mapping, one week assessment, one week report and presentation. Large plants with multiple lines are at the upper end of that range; for very extensive complexes we set the schedule individually after scoping.
Does OT audit meet NIS2 requirements?
Yes. OT audit is part of NIS2 requirements for critical infrastructure operators. Our report documents compliance with NIS2 requirements for OT/ICS systems.
What if you find critical vulnerabilities?
We inform immediately (on-site during audit). We don't wait for final report if something needs urgent response. We'll help with emergency mitigation if needed.