Performing OT Vulnerability Assessment with Claroty

When to Use

• When conducting scheduled OT vulnerability assessments per IEC 62443 or NERC CIP requirements
• When deploying Claroty xDome for the first time and performing initial asset discovery and risk assessment
• When correlating newly published ICS-CERT advisories against your OT asset inventory
• When prioritizing OT vulnerability remediation with limited maintenance windows
• When generating compliance evidence for CIP-010-4 vulnerability assessment requirements

Do not use for active vulnerability scanning of PLCs and safety systems (see performing-ot-network-security-assessment for passive approaches), for IT-only vulnerability management (see standard vulnerability scanners), or for penetration testing (see performing-ics-penetration-testing).

Prerequisites

• Claroty xDome or CTD (Continuous Threat Detection) deployed with sensors on OT network
• Network SPAN/TAP access for passive asset discovery
• CISA ICS-CERT advisory subscription for vulnerability tracking
• Asset inventory with firmware versions for all OT devices
• Change management process for patch deployment during maintenance windows

Workflow

Step 1: Configure Asset Discovery and Vulnerability Correlation

Configure Claroty to perform passive and active-safe discovery to build complete asset inventory with firmware versions for vulnerability correlation.

#!/usr/bin/env python3
"""OT Vulnerability Assessment Manager.

Correlates OT asset inventory with ICS-CERT advisories and CVE data
to identify, prioritize, and track OT vulnerabilities. Designed to
integrate with Claroty xDome API or standalone operation.
"""

import json
import sys
from collections import defaultdict
from dataclasses import dataclass, field, asdict
from datetime import datetime

import requests


@dataclass
class OTAsset:
    asset_id: str
    name: str
    vendor: str
    model: str
    firmware_version: str
    asset_type: str  # PLC, HMI, RTU, historian, switch, etc.
    purdue_level: str
    ip_address: str
    protocol: str
    criticality: str  # critical, high, medium, low
    zone: str


@dataclass
class OTVulnerability:
    vuln_id: str
    cve_id: str
    title: str
    severity: str  # critical, high, medium, low
    cvss_score: float
    affected_vendor: str
    affected_product: str
    affected_versions: str
    description: str
    ics_cert_advisory: str = ""
    remediation: str = ""
    patch_available: bool = False
    compensating_controls: str = ""


@dataclass
class RiskAssessment:
    asset: OTAsset
    vulnerability: OTVulnerability
    risk_score: float = 0.0
    risk_rating: str = ""
    exploitability: str = ""
    operational_impact: str = ""
    compensating_controls: list = field(default_factory=list)
    remediation_priority: int = 0


class OTVulnerabilityAssessment:
    """OT vulnerability assessment and prioritization engine."""

    def __init__(self):
        self.assets = []
        self.vulnerabilities = []
        self.risk_assessments = []

    def load_assets(self, assets_data):
        """Load asset inventory from Claroty export or manual inventory."""
        for a in assets_data:
            self.assets.append(OTAsset(**a))
        print(f"[*] Loaded {len(self.assets)} OT assets")

    def fetch_ics_advisories(self):
        """Fetch latest ICS-CERT advisories from CISA."""
        print("[*] Fetching ICS-CERT advisories from CISA...")
        try:
            # CISA Known Exploited Vulnerabilities catalog
            url = "https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json"
            resp = requests.get(url, timeout=30)
            resp.raise_for_status()
            data = resp.json()

            ics_vulns = []
            for vuln in data.get("vulnerabilities", []):
                # Filter for ICS-relevant vendors
                ics_vendors = [
                    "siemens", "schneider", "rockwell", "honeywell",
                    "abb", "ge", "emerson", "yokogawa", "omron",
                    "mitsubishi", "phoenix", "moxa", "advantech",
                ]
                vendor = vuln.get("vendorProject", "").lower()
                if any(v in vendor for v in ics_vendors):
                    ics_vulns.append(vuln)

            print(f"  Found {len(ics_vulns)} ICS-relevant known exploited vulnerabilities")
            return ics_vulns

        except Exception as e:

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