When you install software on your computer, you accept terms of use that you probably never read. Behind these mechanical clicks lies a technical choice: who really controls the program you use every day? Free software offers a clear answer to this question by giving users full access to the source code and the ability to modify it.
What open source code changes for cybersecurity
Have you ever noticed that proprietary software asks you to trust it without ever showing how it works? With free software, the source code is readable by everyone. Any developer can check what the program actually does with your data.
This transparency has a direct consequence on security. When thousands of people can review the code, vulnerabilities are spotted faster. A proprietary publisher relies on an internal team to detect its own errors. Free software works like a document proofread by multiple editors: each additional pair of eyes reduces the risk of error.
The community that contributes to projects like Linux or LibreOffice regularly publishes patches. These updates are available immediately, without waiting for a publisher to decide to distribute them. For organizations that handle sensitive data, this responsiveness matters.
Francophone resources like mondelibre.org document these solutions and help navigate the ecosystem of free software, from operating systems to office tools.
Cyber Resilience Act: what European regulation imposes on marketed free software
A rarely addressed angle in comparisons between free and proprietary: regulation. The European Cyber Resilience Act (CRA) introduces new obligations that directly concern free software, depending on its use.
The CRA distinguishes between non-commercial free software and marketed free software. A community project distributed for free, without monetization, is not subject to the same constraints as a company that sells services related to that same software. As soon as a paid offer comes into play (support, hosting, data processing), the company can be considered a manufacturer under the regulation.
Vulnerability notification obligations
Concerned manufacturers must report actively exploited vulnerabilities to their national CSIRT and to ENISA. The initial alert must be transmitted within 24 hours, followed by a detailed notification within 72 hours. Full compliance requirements will apply starting December 11, 2027.
The CRA also creates a status of “open-source software steward.” This term refers to foundations or legal entities that ensure the viability of free software intended for commercial use. These stewards have reduced but real cybersecurity obligations, particularly regarding documentation and vulnerability management policies.
Responsibility of user companies
Integrating a free component into a commercial product does not exempt one from verifying its security. The CRA imposes a duty of care regarding third-party components. If a vulnerability is discovered in an open-source module, the company using it must pass the information to those maintaining that component.
The fact that a component is free does not transfer security responsibility to the community. This clarification changes the game for organizations that rely on free software bricks without contributing to their maintenance.
Free software and personal data protection
Proprietary software sometimes collects usage data (telemetry) without the user being aware. With free software, the source code allows you to verify exactly what information is transmitted, to whom, and for what purpose.
Let’s take a concrete example. A proprietary video conferencing software may send metadata (call duration, participants, usage frequency) to third-party servers. With a free solution like Jitsi, you can host the service on your own infrastructure and maintain full control over the exchanged data.
For local authorities and associations, this point is particularly sensitive. Using solutions whose code is auditable allows for verifiable compliance with GDPR requirements, not just declarative compliance.
Real cost of free software: beyond free
Free does not mean without cost. Most free software can be obtained without licensing fees, but their deployment in a professional context involves other expenses. Confusing them would be a mistake.
- Training teams on new tools takes time, especially when they have been using proprietary solutions for years. A migration to LibreOffice, for example, requires change management support.
- Technical support can be provided by specialized service providers, for a subscription fee. This expense replaces licensing fees, but it exists.
- The absence of licensing fees reduces recurring costs, especially for organizations that deploy the same software on many workstations. The larger the fleet, the more visible the savings.
The real financial gain of free software lies in independence from a single vendor. When a proprietary publisher raises its prices or stops maintaining a product, the captive organization has no immediate alternative. With free software, the code remains available. Another provider can take over.
Open formats and interoperability: avoiding technical lock-in
Have you ever received a file that you couldn’t open because you didn’t have the right software? This problem is called format lock-in. Free software mostly uses open and documented formats, which ensures that your files remain readable over time, regardless of the tool.
The ODF (Open Document Format), for example, is an international standard. A document created with LibreOffice can be opened by any software compatible with this format. A file saved in a proprietary format, on the other hand, depends on the goodwill of the publisher to remain accessible.
- Open formats facilitate exchanges between organizations that do not use the same tools.
- They protect against obsolescence: a document remains readable even if the original publisher disappears.
- Public administrations in several European countries already require open formats for official documents.
Choosing free software also means choosing not to depend on a single supplier to access your own data. This technical autonomy remains one of the most concrete arguments in favor of ethical computing, far beyond philosophical considerations about code freedom.
