IEC 62443: Patch & Vulnerability Management (OT-safe)

    IEC 62443 emphasizes secure maintenance, including patch and vulnerability handling. QuantLayer helps you baseline versions, prioritize risk, and perform OT-safe remediation with auditable change control.

    Patch Management
    Vulnerability Handling
    OT
    8 min
    Last updated: 2026-01-22

    Overview

    Patch management in OT is different from IT: downtime windows are limited, vendor constraints exist, and safety is paramount. IEC 62443 expects organizations to manage vulnerabilities and updates in a controlled, risk-based manner.

    Recommended workflow

    • Baseline: maintain accurate firmware/software inventories by zone and asset class.
    • Assess: evaluate vulnerability exposure and operational impact, prioritize by risk/criticality.
    • Plan: coordinate with operations/vendors, schedule maintenance windows and rollback plans.
    • Execute: perform controlled updates and validate integrity/behavior post-change.
    • Document: record approvals, changes, and outcomes for audit and continuous improvement.

    QuantLayer capabilities

    Version & Posture Inventory: track device OS/firmware/app versions and baseline posture by site, zone, and fleet.

    Risk Signals: prioritize remediation using trust drift indicators such as missing patches, integrity anomalies, and policy violations.

    OT-Safe Enforcement: use staged enforcement and time-bound rules so updates can execute without unexpected access disruptions.

    Evidence outputs

    • Patch posture report by zone/fleet (coverage, exceptions, planned remediation dates).
    • Change approvals and implementation records (who approved, when applied, rollback plan).
    • Integrity validation after changes (secure boot checks, drift detection, verification events).
    Implementation note
    IEC 62443 compliance is achieved through a combination of people, process, and technology controls. QuantLayer helps you operationalize the technical controls (identity, segmentation, integrity, telemetry, response) while producing audit-ready evidence to support your CSMS and assurance activities.