OpenPeppol Moves Toward Mandatory ISO 27001 Certification as Supply Chain Threats Mount

OpenPeppol, the network that underpins electronic invoicing and document exchange across dozens of countries, is preparing to require its service providers to hold ISO/IEC 27001 certification, with the requirement expected to take effect by 2028. The move comes as the organization faces a rapidly evolving threat landscape and growing pressure to demonstrate that its expanding, interconnected network of providers can be trusted.

Why Now

Officials pushing the initiative argue the timing is not incidental. In Europe, the NIS2 directive is already being transposed into national law, and ISO 27001 is recognized as a way to meet those emerging requirements — it is already an accepted certification in some countries, including Belgium. Beyond Europe, the continued growth of OpenPeppol's membership and operations has made the network an increasingly attractive target for attackers worldwide.

A central concern is the network's exposure to supply chain attacks, which have become one of the most common threat patterns facing interconnected digital infrastructure. Because OpenPeppol relies on a complex web of interdependent service providers, a compromise at one point in that chain has the potential to affect the wider network.

Proponents of the certification requirement are careful to note that ISO 27001 is not a snapshot assessment. Rather than certifying that an organization's security was adequate at a single point in time, it certifies an ongoing commitment to security governance — verified through repeated audits — which is intended to give regulators, customers, and partners lasting assurance rather than a one-time guarantee.

The Threats Driving the Push

The organization has outlined a range of threats it says the network must guard against, including:

• Supply chain risk — a weakness at one provider that could ripple across the entire network
• Data breaches and espionage — sensitive business information exposed through a compromised provider
• Operational disruption — outages or incidents at providers interrupting service
• Fraud and data manipulation — transactions or documents that are altered, spoofed, or misused
• Phishing and credential theft — attackers targeting users and administrators to gain unauthorized access
• Ransomware and extortion — attacks that encrypt data or halt operations
• Geopolitical and state-linked threats — heightened risk from advanced, state-connected actors and global instability
• Regulatory fragmentation — inconsistent national rules that undermine unified oversight

Where the Network Is Vulnerable

Alongside these external threats, the organization has flagged a set of vulnerabilities that leave providers within the network exposed, including weak web-application security controls, insecure session and cookie handling that risks account takeover, missing browser security headers, outdated encryption protocols, gaps in patch management, and publicly exposed infrastructure that widens the potential attack surface. Security maturity is also said to vary significantly from provider to provider, creating uneven resilience across the network — and officials caution that certification alone is not synonymous with strong technical controls.

Building a "Security Floor"

Backers of the certification requirement frame it as more than a compliance checkbox. They describe it as a way to establish a common security baseline — or "security floor" — across all participants, allowing service providers to exchange documents with any other access point in the network without needing to conduct bilateral due diligence on each partner's security practices. The policy is also intended to give providers a single, clear security standard to follow, rather than having to interpret differing expectations across every jurisdiction in which OpenPeppol operates.

As Peppol increasingly becomes embedded in national tax and procurement systems, officials say the stakes are rising: a serious security failure could damage confidence not just in a single provider, but in the network's reputation as a whole, with broader economic consequences. A unified security baseline, they argue, helps lower that systemic risk.

Bridging the Gap Until Certification

While ISO 27001 certification is already mandated in principle, officials acknowledge that full certification is a lengthy process and that security threats will not wait for it to be completed. To close that gap, OpenPeppol is considering a set of interim security requirements that would establish a baseline of good security practice for providers while the certification process is still underway, even though those interim measures would ultimately become redundant once ISO 27001 certification is in place.

This content is intended to share insights and practical considerations based on industry experience. It does not constitute legal, regulatory, or financial advice. Regulatory requirements vary by jurisdiction and circumstance, so any compliance-related matters should be reviewed and validated with your own professional advisors.