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Qt Open Source and Commercial Licensing Towards CRA in Industrial Automation

Written by Qt Group | May 12, 2026 11:35:32 AM
Venla Pouru

Director, Industries, Qt Group

Amit Nainawat 

Director, Solutions Engineering, Qt Group

The EU Cyber Resilience Act (CRA), Regulation (EU) 2024/2847, came into force on 10 December 2024. From 11 September 2026 manufacturers placing a product with digital elements (PDE) on the EU market must comply with the CRA's vulnerability reporting obligations; from 11 December 2027 the full set of essential cybersecurity requirements applies to any such product placed on the market for the first time. Compliance to CRA will not be a nice-to-have. Penalties under CRA Article 64 reach up to EUR 15 million or 2.5% of total worldwide annual turnover for the preceding financial year (whichever is higher) for the most serious breaches of the essential requirements.

 

The CRA does not distinguish between products built on open source and products built on proprietary software—the manufacturer of the final PDE carries the obligations either way. For industrial automation manufacturers—programmable logic controllers (PLCs), human-machine interfaces (HMIs), supervisory control and data acquisition (SCADA) front-ends, etc—this changes the substance of the choice between Qt Community Edition and commercial Qt.

Some structural characteristics of Qt Community Edition become material constraints under CRA. First, the Qt Project is an open source steward under CRA, not a manufacturer, so it cannot supply the conformity artifacts the manufacturer needs. Second Qt Community Edition's security update timing is structurally misaligned with the CRA's reporting clocks, and the user is left to produce and maintain the full compliance documentation independently.

CRA does not distinguish between products built on OSS and products built on proprietary software—the manufacturer carries the obligations either way.

 

Commercial Qt closes those gaps with a five-year Long-Term Support (LTS) maintenance window from Qt 6.8 onward, immediate security patches, SBOM coverage and Qt Group conformity inputs intended to support customer technical documentation, and documented vulnerability handling under Qt Group's role as a CVE Numbering Authority (CNA). 

 

The same documentation Qt Group produces for CRA can be reused directly in a IEC 62443 conformity file.

 

The CRA Has Rewritten the Open Source Equation

For years, the choice between Qt Community Edition and commercial Qt in industrial automation has been framed as a trade-off between upfront cost and convenience. The EU Cyber Resilience Act (CRA) has rewritten that equation.

Manufacturers placing PDE on the EU market after 11 December 2027 must demonstrate with evidence, documentation, and auditable processes that every component in the stack meets the CRA's essential cybersecurity requirements. That includes the GUI framework.

Any manufacturer placing a PDE on the EU market—regardless of origin—carries the full obligations.

This article examines what the CRA actually requires, what Qt Community Edition can and cannot cover, and where commercial Qt closes the gap.

List of Abbreviations

CE marking—Conformité Européenne marking—manufacturer's declaration of conformity with applicable EU regulations
CNA—CVE Numbering Authority
CRA—EU Cyber Resilience Act (Regulation (EU) 2024/2847)
CVE—Common Vulnerabilities and Exposures
ES—Extended Support (Qt commercial service)
ESM—Extended Security Maintenance (Qt commercial service)
GPL—GNU General Public License
GUI—Graphical User Interface
IEC—International Electrotechnical Commission (e.g. IEC 61508, IEC 62443)
LGPL—GNU Lesser General Public License
LTS—Long-Term Support
PDE—Product with Digital Elements (CRA term)
PLC—Programmable Logic Controller
SBOM—Software Bill of Materials
SCADA—Supervisory Control and Data Acquisition
TLS—Transport Layer Security
24h/72h/14d Incident Reporting Guide—the obligation to issue an early warning within 24 hours of an actively exploited vulnerability, a full notification within 72 hours, and a final report within 14 days of corrective measures available

CRA Sets the Bar

According to CRA, any manufacturer placing a PDE on the EU market—regardless of origin—carries the full obligations. The essential requirements (CRA Annex I) include, among others:

  • Security by design and default across the product lifecycle—no known exploitable vulnerabilities at delivery, secure default configurations, protection against unauthorized access, and confidentiality and integrity of stored, transmitted, and processed data.

  • Vulnerability handling under CRA Article 14—early warning to the relevant CSIRT and to ENISA within 24 hours of an actively exploited vulnerability becoming known, full notification within 72 hours, and a final report within 14 days of corrective measures being available (24h/72h/14d Incident Reporting Guide).

  • Security updates free of charge for the product's support period (default five years).

  • SBOM covering every third-party component, including open source dependencies.

  • Due diligence on third-party components, explicitly including free and open source components.

  • Technical documentation (CRA Annex VII) demonstrating conformity, with successful conformity assessment authorizing the manufacturer to issue the EU declaration of conformity and affix the CE marking.

The reporting clock starts when an actively exploited vulnerability becomes known, not when the manufacturer decides to act. Responsibility for third-party components rests with the manufacturer of the final product. If an industrial HMI uses Qt and a critical vulnerability is found in Qt, the HMI manufacturer must address it—whether using Qt Community Edition or commercial Qt.

 

Responsibility for third-party components rests with the manufacturer of the final product.

What Qt Community Edition Covers—and What It Does Not

Qt Community Edition is Qt distributed under the LGPL for most modules, with a smaller set of modules under the GPL. It is a legitimate choice for teams at the prototyping stage, for internal-only tooling that is not placed on the EU market, for research or educational projects without commercial distribution. 

 

Where Commercial Qt Closes the Gap

Qt Community Edition vs. Commercial Qt Under the CRA

Practical Implications for Industrial Automation Teams

What Qt Group Recommends