OT/ICS Penetration Testing
OT systems have critical vulnerabilities - unpatched PLCs, SCADA without authentication, industrial protocols without encryption. We'll find them with controlled methods, without stopping production. You get a remediation roadmap.
What is OT/ICS Penetration Testing?
OT/ICS Penetration Testing is the controlled, safety-first attempt to exploit vulnerabilities in industrial control systems — SCADA, PLC, DCS, HMI, and industrial protocols — using methods specifically adapted to avoid production downtime. nFlo follows a tiered approach (passive reconnaissance → active scanning → controlled exploitation) and delivers a remediation roadmap with risk priorities; 75% of OT systems carry critical vulnerabilities, yet standard IT pentests are too aggressive for these sensitive environments.
OT vulnerabilities can stop production - attackers know this
Penetration testing adapted to OT specifics
Passive Recon
Map systems without interference
Safe Testing
Methods adapted to OT sensitivity
Remediation Roadmap
Prioritization and action plan
Florida Water Treatment Plant - Hacker Increased Chemical Concentration
In February 2021, an attacker remotely gained access to SCADA at a water treatment plant and increased sodium hydroxide concentration to toxic levels. The operator noticed the change and manually reversed it - the attack could have ended in tragedy.
Without OT penetration testing:
- Critical vulnerabilities remain unknown until attack
- Standard IT pentests are too aggressive for sensitive OT systems
- No prioritization - you don’t know what to patch first
- Risk of production downtime during “unexpected” security test
- Non-compliant with NIS2 and IEC 62443 testing requirements
OT Pentests Without Production Risk
We use methodology adapted to industrial environment specifics. We know which tests are safe for SCADA, PLC and industrial protocols. We don’t stop production.
What you get:
- Passive OT system inventory (network mapping without interference)
- Industrial protocol analysis (Modbus, Profinet, OPC UA, etc.)
- Safe SCADA/HMI vulnerability tests
- IT/OT network segmentation verification
- Permissions and access control testing
- Attack simulation on unencrypted protocols
- Report with risk assessment and priorities
- Support during fix implementation
- Optional retest after implementation
Who Is It For?
This service is for you if:
- You use SCADA, DCS, PLC systems in production
- You need to meet NIS2 or IEC 62443 security testing requirements
- You’re concerned that standard IT pentest could stop production
- You need to verify IT/OT segmentation effectiveness
- You’ve implemented security controls and want to check if they work
Our Methodology
Production Safety is Priority
OT pentests differ from IT tests - we can’t allow downtime. Our approach:
1. Pre-engagement
- Detailed scope and limitations discussion
- Defining “red lines” - what we DON’T test
- Communication plan with maintenance team
- Time window and alarm procedures
2. Passive Reconnaissance (Tier 1)
- Network traffic sniffing (without sending packets)
- Topology analysis and asset identification
- Documentation and configuration review
- Safe for production: YES
3. Active Scanning (Tier 2)
- Port and service scanning
- SCADA/PLC system fingerprinting
- Vulnerability detection (CVE)
- Requires: OT coordination, time window
4. Exploitation (Tier 3)
- Controlled exploitation of selected vulnerabilities
- Test on test environment or after system shutdown
- Requires: isolation or downtime
5. Reporting & Remediation
- Detailed report with risk assessment
- Prioritization by production impact
- Workshop with team
- Optional retest
Test Scope
What We Test in OT Environment
Network Segmentation:
- IT/OT routing
- Industrial firewalls
- VLANs and ACLs
- DMZ for HMI/SCADA
SCADA/HMI Systems:
- Authentication and authorization
- Application vulnerabilities (CVE)
- Hardcoded credentials
- Remote access (VPN, RDP)
Field Devices (PLC, RTU, IED):
- Industrial protocols (Modbus, DNP3, IEC 104, etc.)
- Firmware and versions
- Default credentials
- Engineering workstations
Communication Protocols:
- Missing authentication
- Missing encryption
- Replay attack possibility
- Man-in-the-middle
Physical Security:
- Control cabinet access
- Unsecured Ethernet ports
- USB and Serial
- Engineering laptops
Related Glossary Terms
Learn more about key concepts related to this service:
Contact your account manager
Discuss OT/ICS Penetration Testing with your dedicated account manager.
How we work
Our proven service delivery process.
Kick-off
Define scope and safety rules
Passive Analysis
Network and system mapping without active tests
Controlled Tests
Safe vulnerability verification
Report
Detailed report with risk assessment
Retest
Verification of implemented fixes
Benefits for your business
What you gain by choosing this service.
Find Vulnerabilities First
Before attackers or auditors do
Prioritize Actions
Know what to fix first and why
Avoid Downtime
Vulnerability found in pentest isn't a cyberattack
NIS2 Compliance
Meet regular security testing requirement
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Read more →Frequently Asked Questions
Common questions about OT/ICS Penetration Testing.
How much do OT/ICS penetration tests cost?
Small plant (1-2 lines, basic SCADA): €9,500-14,000. Medium (multiple lines, DCS): €19,000-28,000. Large industrial complex: €38,000+. Price includes passive and active testing, report, and presentation.
Can OT pentest stop production?
Passive analysis (Tier 1) - no. Active tests (Tier 2-3) are performed only after coordination with maintenance team, in a time window or on test systems. You have full control over scope.
How does OT pentest differ from OT audit?
Audit is documentation and configuration review (compliance check). Pentest is active attack attempt - we test whether vulnerabilities can actually be exploited. Both complement each other. We recommend: audit first, then pentest.
How long does OT pentest take?
Typical project is 2-4 weeks depending on environment size. For small plant (1-2 lines) it's 2 weeks, for large industrial complex 4-6 weeks.
How often to repeat OT pentests?
We recommend every 12-24 months or after significant architecture changes. For critical infrastructure NIS2 requires regular tests - minimum once a year.