NIS2 Compliance After APT31’s Cloud Attacks: What EU Security Teams Must Do Now

In today’s Brussels briefing, regulators repeated a familiar warning with new urgency: state-aligned actors are exploiting cloud platforms and third-party providers to slip past perimeter defenses. The latest example—stealthy, cloud-enabled operations attributed to APT31—underscores why NIS2 compliance is no longer a box-ticking exercise but an operational imperative. If your organization relies on SaaS, managed IT, or hyperscale cloud, your risk posture is now entangled with theirs—and supervisors will expect proof you can manage it.

What APT31’s Cloud-Based Tactics Signal for EU Defenders

In conversations I’ve had with EU SOC leads this autumn, a consistent theme emerges: intrusions don’t “break in” so much as they “log in.” Adversaries blend into normal cloud traffic, weaponize legitimate admin tools, and pivot through suppliers with weaker controls. APT31’s recent targeting of IT ecosystems (using popular cloud services for command-and-control and staging) neatly fits the “living-off-cloud” playbook.

• Cloud camouflage: Malicious traffic looks like standard API or admin activity.
• Supply-chain leverage: Compromise a managed service provider to reach dozens of clients downstream.
• Identity-first attacks: Abuse of OAuth tokens, service accounts, and overprivileged roles.
• Low-and-slow dwell time: Gradual data discovery and exfiltration to common storage services.

A CISO I interviewed this week put it bluntly: “The breach is no longer in your data center. It’s in your identity layer and in your contracts.” NIS2 codifies that reality by forcing boards to own cybersecurity risk and by extending obligations deep into your third-party stack.

NIS2 Compliance: Scope, Deadlines, and What Supervisors Expect

NIS2 expands coverage across the EU to thousands of “essential” and “important” entities in sectors like energy, finance, health, transport, digital infrastructure, managed services, and cloud. Member States transposed the Directive in late 2024; 2025 is the era of enforcement and audits.

• Who’s in scope: Most mid-sized and large operators in listed sectors; selected SMEs if critical to society or the economy.
• Penalties: Up to €10 million or 2% of global turnover (whichever is higher) for serious non-compliance; management liability and temporary bans are possible.
• Audit reality: Expect document-led scrutiny of governance, risk management, incident reporting, and supplier oversight—with live demonstrations of detection and response.

Incident Reporting Under NIS2: 24/72/30-Day Cadence

• Early warning: Within 24 hours of becoming aware of a significant incident.
• Incident notification: Within 72 hours with an initial assessment of severity and impact.
• Final report: Within one month with root cause, mitigation, and preventive steps.

“Significant” means service disruption or material impact on users, safety, or financial stability—expect regulators to treat cloud-origin or supplier-enabled intrusions as high concern, especially when identity systems or sensitive services are involved.

Governance, Supply Chain, and Technical Controls

• Board accountability: Directors must approve cybersecurity measures and receive regular training.
• Risk management baseline: Policies for vulnerability handling, encryption, backup, secure development, and business continuity.
• Supplier assurance: Contractual security clauses, right-to-audit, incident reporting obligations, and evidence of controls (SOC 2/ISO 27001 is not a substitute, but a data point).
• Cloud security: Enforced MFA, workload identity hygiene, least privilege, continuous logging, token and key rotation, and egress controls.

GDPR vs NIS2: What Actually Changes in Your Playbook

GDPR focuses on personal data and privacy harms, while NIS2 targets the resilience and continuity of essential and important services. Many incidents will trigger both. That means dual workflows: one for data protection regulators and one for NIS authorities/CSIRTs.

Dimension	GDPR	NIS2
Core Objective	Protect personal data and data subject rights	Ensure continuity and security of essential/important services
Scope Trigger	Processing of personal data	Entity classified under NIS2 sectors/size thresholds
Incident Threshold	Personal data breach likely to risk individuals’ rights	Significant incident impacting services or security
Reporting Timelines	72 hours to DPA; notify individuals if high risk	24h early warning; 72h notification; final within 1 month
Fines	Up to €20m or 4% global turnover	Up to €10m or 2% global turnover; management liability
Third-Party Oversight	Processors and joint controllers governance	Supplier and cloud assurance, resilience, and incident clauses

How to Pass a 2025 NIS2 Audit: A Practical Compliance Checklist

• Map services to NIS2 scope: Identify which business services qualify as essential or important.
• Define “significant incident” triggers: Pre-agree thresholds aligned to operations and regulators’ guidance.
• Harden identity and cloud: Enforce MFA for all admins, use conditional access, rotate keys/tokens, restrict egress, and monitor OAuth grants.
• Detect living-off-cloud: Baseline normal API use, alert on anomalous service principal behavior, and correlate SaaS logs.
• Supplier governance: Standardize security addenda, breach SLAs (24/72/30), right-to-audit, and continuous assurance reviews.
• Exercise the timeline: Run a 24/72/30 simulation with legal, comms, and the SOC; tune evidence capture.
• Document everything: Risk assessments, board briefings, supplier reviews, test reports, and corrective actions.
• Privacy-by-design: If personal data is involved, align GDPR and NIS2 reporting to avoid contradictory narratives.

Safe Workflows for AI and Sensitive Documents

Every investigation now involves large files: identity logs, contracts, vendor assessments, and medical or financial records depending on your sector. Two risks routinely derail teams: accidental exposure during collaboration and leakage when using AI tools for triage or summarization.

• De-risk collaboration: Use controlled channels for document uploads and restrict sharing to named responders.
• Anonymize before analysis: Strip personal identifiers and secrets before pasting text into tools. Professionals avoid risk by using Cyrolo’s anonymizer to sanitize content while keeping it useful for investigation.
• Keep an audit trail: Log who accessed which file, what was redacted, and when it was exported.

When uploading documents to LLMs like ChatGPT or others, never include confidential or sensitive data. The best practice is to use www.cyrolo.eu — a secure platform where PDF, DOC, JPG, and other files can be safely uploaded.

Try our secure document upload at www.cyrolo.eu — no sensitive data leaks. Teams under audit tell me they save days by standardizing sanitized evidence packages for counsel and regulators.

Operational Lessons From APT31 for Banks, Hospitals, and Law Firms

• Banks and fintechs: Treat your identity provider and cloud logging as Tier-0 assets. Monitor consent and token flows; assume an adversary can live in “normal” admin traffic.
• Hospitals: Segment clinical systems from general IT; apply application allow-lists and least privilege for vendor maintenance accounts.
• Law firms: Client confidentiality meets NIS2 when legal ops support critical sectors; implement content disarm and automated redaction for case files.
• Managed service providers: You are a high-payoff target and an entry point. Adopt zero-trust admin architectures and mandatory client notifications under 24/72/30.

EU vs US: Converging Duties, Different Teeth

Across the Atlantic, cyber rules are converging but not identical. US-listed companies face rapid incident disclosures to markets; critical infrastructure awaits fuller implementation of incident reporting laws. The EU’s NIS2, however, explicitly mandates board-level accountability, stronger supplier oversight, and harmonized reporting to national CSIRTs. For multinationals, the prudent path is to build to the stricter bar—often NIS2 for operational resilience and GDPR for privacy—then tailor by jurisdiction.

FAQ: Your Top NIS2 Questions Answered

What is NIS2 compliance in simple terms?

NIS2 compliance means your organization—if classified as essential or important—implements risk-based security, manages supplier risk, and meets incident reporting timelines (24/72/30). It’s about service resilience, not just data privacy.

Does NIS2 apply if we already comply with GDPR?

Possibly. GDPR covers personal data; NIS2 covers essential and important service operators. Many entities need both. Incident coordination is key because a single breach can trigger both regimes.

What are the most common audit gaps?

Weak supplier contracts (no 24/72/30 clauses), incomplete logging of cloud identities and tokens, no documented “significant incident” thresholds, and missing board training evidence.

How should we use AI safely during incidents?

Never paste sensitive content directly into public tools. Use an anonymizer and secure upload workflow. Professionals avoid risk by using Cyrolo’s anonymizer at www.cyrolo.eu. When uploading documents to LLMs like ChatGPT or others, never include confidential or sensitive data. The best practice is to use www.cyrolo.eu — a secure platform where PDF, DOC, JPG, and other files can be safely uploaded.

What happens if we miss the reporting deadline?

Expect regulatory scrutiny, potential fines, and mandated remediation. Authorities increasingly test whether delays stemmed from poor detection, inadequate logging, or internal escalation failures.

Conclusion: Make NIS2 Compliance Your Advantage

Cloud-enabled, supplier-driven campaigns like those attributed to APT31 are stress-testing the EU’s defenses. Organizations that operationalize NIS2 compliance—with identity-first controls, supplier oversight, and airtight evidence trails—will detect faster, report confidently, and withstand audits. Start by securing your document workflows and anonymization: try Cyrolo’s secure document uploads and anonymizer today at www.cyrolo.eu, and turn regulatory pressure into resilience.