Executive Summary

The AWS US-EAST-1 outage on October 20, 2025 demonstrated, once again, that the backbone of Europe’s essential digital services remains tightly, and opaquely, tethered to an Amazon data center cluster in Virginia. European banks, national agencies, and healthcare providers all went dark when a DNS issue in the United States cascaded through global authentication and service management systems, taking down hundreds of companies and affecting millions of users. The incident exposed uncomfortable truths, not just about technical resilience, but also about transparency and compliance with GDPR. Even when EU companies believe their IT operations and data are limited to European regions, hidden architectural dependencies on US-EAST-1 can bring both outages and legal risks. Most critically, end users rarely know when their data, or command functions affecting their data, transit international boundaries.

This article analyses the technical anatomy of the October 2025 AWS outage, identifies specific European companies and sectors hit hardest, and investigates the transparency and compliance failures that allowed a US incident to reverberate throughout the EU. It also explains implications under Schrems II, exposes weaknesses in AWS’s terms of service for European customers, and calls for European CIOs and regulators to demand stronger guarantees, or face a recurrence that risks both business continuity and core data protections.

Table of Contents

• What Happened in US-EAST-1, October 2025

• Why a US Outage Grounded European Digital Life

• European Companies Hit the Hardest

• The GDPR and the Cloud: What Users and Companies Don’t Know

• Schrems II: The Legal Earthquake Beneath the Outage

• AWS Agreements and Regional Dependence

• Transparency Failures and Hidden Data Transfers

• Sidebars: How IAM Ties Everything Back to America

• Is “Cloud” Just Another Person’s Computer?

• What CIOs Should Do Now

• DPA and Regulatory Reactions

• Conclusion

What Happened in US-EAST-1, October 2025

Shortly after midnight US Pacific Time, AWS’s US-EAST-1 region experienced a failure involving DNS resolution for DynamoDB API endpoints. While the alleged initiating event was a technical update that corrupted DNS records, the specific configuration at fault impacted much more than a single database cluster. Amazon’s engineers accelerated into incident mode, pushing patches and throttling operations for EC2, SQS, Lambda, and more. However, as service after service attempted retries, client requests quickly flooded internal networks, jamming queues and causing backlogs throughout the dependent stack. Over seven hours passed before most status dashboards read “operational” again, and hundreds of millions of users worldwide experienced partial or total outages.​

Anatomy of Catastrophe

AWS regions are advertised as isolated units, each with independent infrastructure and redundancy. Yet global AWS services including IAM, CloudFront, Route53, Lambda@Edge, and Certificate Manager rely on centralized control-plane endpoints, almost all rooted in US-EAST-1. When these core management, authentication, or API orchestration services go down, so do the workloads that depend on them, regardless of where companies choose to host their actual data and compute.​

Why a US Outage Grounded European Digital Life

For European companies and agencies that believed their systems were safe within eu-west-1 (Ireland), eu-central-1 (Frankfurt), or other EU regions, the AWS incident was a rude awakening. Many of the core platform control-plane services especially for authentication, permissions management, and certain orchestration tasks are centralized in Virginia. Key operations, from launching a new instance to refreshing a user’s permissions, implicitly depend on US-EAST-1. Even if no primary data is stored in the US, architectural dependencies and “global” API calls route through American servers. During the outage, banks in the UK, the Netherlands, Belgium, and Germany all reported severe disruptions. National agencies, including Britain’s HM Revenue & Customs (HMRC), and even the European Commission’s digital platforms, went dark or experienced severe performance degradation.​

Real-World Impact Examples

• Banking: Lloyds Bank, Bank of Scotland, fintech trading platforms, and the UK’s tax and payments authority all went offline, exposing a direct risk to critical national infrastructure.​

• Healthcare: Hospitals and clinics lost access to digital records, affecting patient care and critical operations.​

• Government: HMRC, European Commission, and similar public sector bodies dependent on AWS for communications and workflows reported disruptions. EU institution service portals were cited as dysfunctional by mid-morning.​

• Automotive Manufacturing: Major OEMs running cloud-based supply chain and production management systems were left idle, illustrating risks not only to consumer apps but also to essential industrial infrastructure.​

• Other: Messaging apps (WhatsApp, Signal, Snapchat), gaming platforms, e-commerce, and airline operations all saw failures.​

European Companies Hit the Hardest

European reliance on the cloud runs deeper than most citizens, let alone policymakers, realize. Financial services (Barclays, Lloyds, HSBC), e-government (HMRC, Parliament tools), healthcare providers (NHS digital health records, hospital systems), and telecoms (Vodafone, BT) were all confirmed as significantly impacted. In some cases, the disruption was not merely to public-facing digital services but to vital backend operations that underpin regulatory, health, and commercial infrastructure.​

Of particular concern:

• Banks and financial markets: Transactional platforms went dark. Trading desks, digital payments, and online banking applications failed at a time when global markets were open and active.

• Health and emergency systems: Blocked access to records and system authentication; direct risks to patient safety and response coordination.

• National Revenue Authorities: Shutdowns and unavailability for government tax, customs, and payments operations, exposing societies to broader risks than lost shopping carts or entertainment downtime.

These sectors process and store sensitive personal information, making the dependency on cross-Atlantic services, and by extension, US legal oversight, even more concerning from both a security and a legal standpoint.

The GDPR and the Cloud: What Users and Companies Don’t Know

Hidden Cross-Region Dependencies

The General Data Protection Regulation (GDPR) is unambiguous: European data must be protected according to principles of security, integrity, and (crucially) transparency regarding where and how data is processed. Yet architectural choices made by AWS, and often by developers unaware of the fine print, mean that EU-located workloads may still silently route user commands or backup data through US-EAST-1. Many companies leave SDKs and toolkits on the default region, US-EAST-1, unintentionally centralizing critical permission and orchestration functions in the United States. End users, for their part, are rarely notified when their personal data, or operations affecting it, traverse US borders or rely on US-based control infrastructure.​

“When a service needs to refresh or obtain their permissions, IAM is queried. Hence, the more global outage.” (HMRC staff comment)​

Transparency and Notification Failures

AWS maintains that customer data remains in the region specified by the customer, except as necessary for certain operations, troubleshooting, or as required by law. However, AWS’s terms do not require prior notification to end users, or even to account holders, regarding cross-region dependencies for control-plane operations or failover events, except in cases of explicit multi-region replication or legal compulsion.​

This lack of transparency may conflict with GDPR’s requirements for clear information to data subjects about where and how their data is processed, especially when services implicitly depend on US-based resources for authentication, access control, or system management.

Schrems II: The Legal Earthquake Beneath the Outage

What is Schrems II?

Schrems II refers to the 2020 decision by the Court of Justice of the European Union (CJEU) that invalidated the EU-US Privacy Shield as a lawful mechanism for sending personal data from the EU to the US. It upheld the use of Standard Contractual Clauses (SCCs), but only if supplementary measures sufficiently protect EU data from US government surveillance and meet the high bar for privacy established by the GDPR.

Implications for the Outage

AWS, like all hyperscalers, now relies on SCCs and supplementary technical and contractual controls for transatlantic data flows. However, as documented in DPA guidance, true Schrems II compliance is difficult when a core component such as IAM or DynamoDB’s control plane is both architecturally and legally resident in the US, subject to US surveillance under FISA and other statutes.​

Despite AWS offering encryption and “bring your own key” (BYOK) options, DPA investigations have highlighted the risk that US-based staff, or US government authorities, could compel disclosure, even of data that nominally “never leaves Europe” but is touched by cross-region operations or logging metadata.​

Many DPAs have issued guidance warning of the risks with cloud providers and are investigating, especially regarding critical infrastructure and sensitive public-sector contracts. The European Data Protection Supervisor has opened specific proceedings regarding the “Cloud II” contracts used by EU authorities with AWS and Microsoft.​

AWS Agreements and Regional Dependence

Fine Print and “Region” Myths

AWS’s Customer Agreement and Service Terms declare commitments to keep customer content in chosen regions, but with broad exceptions. These include circumstances where AWS needs to maintain or troubleshoot services, comply with law, or support global features like account management and IAM control.​

The Amazon Compute SLA, for instance, promises 99.99 percent availability per region for EC2 if workloads are distributed across availability zones, but does not account for failures in global services like IAM. Credits are available for outages below the promised threshold but, as customers discovered, the real systemic risk comes not from “regional” failures but from the hidden centralization of global control planes in US-EAST-1.​

“Some AWS features (for example global account-management, IAM, some control APIs, or even replication endpoints) are served from US-EAST-1, even if you’re running workloads in Europe. If those services go down or become very slow, even European workloads may be impacted.”​

What the EOA and Service Agreements Say

The AWS Data Processing Addendum (DPA), incorporated by reference into the AWS Service Terms, includes SCCs but specifically allows AWS to transfer data or metadata as necessary for maintaining global account services, even within EU-only contracts. The DPA does not require explicit user notification when such routing occurs, despite strong requirements for informing data subjects under GDPR. Most “Global” features (IAM, CloudFront, Lambda@Edge) expressly depend on US-EAST-1, a fact not always revealed to end customers or even to DevOps teams at EU corporations.​

Transparency Failures and Hidden Data Transfers

Despite the promises of “local” cloud regions, the technical reality is that AWS’s architecture can allow a US region’s misconfiguration or failure to break systems running solely in Europe. The control plane, managing identities, permissions, configuration state remains a single point of global failure present in nearly every European deployment, except for the newly announced European Sovereign Cloud (which remains unavailable for most workloads as of October 2025).​

European customers, especially in privacy-sensitive industries like finance, health, and government, are left unable to independently verify how often their operations or metadata traverse borders. The scale and opacity of AWS’s metadata handling, debugging activity, and platform event logging make it nearly impossible for regulated companies to prove (or disprove) that personal data remained entirely within European jurisdiction during an incident or failover.

The Single Point of Global Failure

IAM (Identity and Access Management) is the beating heart of AWS’s global architecture. Even when creating backup roles or making policy adjustments in a European region, the logical “source of truth” and key change-management APIs are rooted in US-EAST-1. During the October 2025 outage, companies with operations exclusively in EU regions found they could not authenticate sessions, launch failover instances, or update access policies simply because the IAM control plane in Virginia was unreachable.

Is “Cloud” Just Another Person’s Computer?

This outage has made it clear that “the cloud is just another person’s computer”, but in this case, it’s someone in another country, with their own priorities, legal constraints, and business drivers. European organizations rent stability from AWS, but the underlying physical and management control rests with a corporation bound by US law and business interests. The lockdown was a consequence of this transfer of control, and the legal ambiguities of GDPR compliance when a third party holds the technical levers even from across the Atlantic.

What CIOs Should Do Now

Action Checklist

1. Map all dependencies for control-plane services in AWS workloads. Do not assume “regional” means “sovereign.”

2. Review all IAM, Route53, Certificate Manager, and Lambda@Edge configurations for cross-region default settings. Explicitly set region for all core services and enforce regional access wherever possible.

3. Review contracts and the AWS DPA addendum, especially for critical workloads. Consult legal counsel on implications of technical and contractual exceptions allowing metadata or operational transfers.

4. Conduct technical due diligence on whether key operational commands can be executed (and redundancy maintained) without cross-region dependencies.

5. Demand transparency from AWS regarding which services have control-plane components in other regions and push for roadmaps that localize these functions in Europe.

6. Review national DPA and EDPS guidance. Prepare for potential regulatory action if compliance with Schrems II or GDPR data locality requirements cannot be guaranteed during outages or routine operations.

7. Test and drill failover and disaster recovery scenarios, including cases where global authentication and naming services become unavailable from US-EAST-1.

DPA and Regulatory Reactions

Official and Sector Guidance

European data protection authorities (DPAs), notably the European Data Protection Supervisor (EDPS), have already launched investigations into the impact of “Cloud II” style contracts and the adequacy of supplementary measures guaranteed by AWS after Schrems II. The consensus: While encryption and keys offer some protection, if US-based corporate entities hold technical or legal access to operational metadata, or even encrypted customer content true compliance remains questionable. National DPAs are increasing scrutiny and may impose further requirements or restrict usage for sensitive sectors like public administration, critical infrastructure, and health.​

Notably, these issues remain on the agenda at the highest political levels in Brussels. Sovereignty, transparency, and technical resilience all hang in the balance as leaders debate how to ensure the next outage won’t plunge European life, or personal data, into American jurisdiction by stealth.​

Conclusion

Europe’s dependency on the US-based AWS US-EAST-1 region has proved not just to be a technical weak spot, but a legal and compliance minefield. Outages are no longer local, they are global events with regulatory and reputational consequences. The tragedy is that most users, and even many corporate clients, remain unaware of the true complexity and risk hidden beneath the cloud’s surface.

Until the architecture of the internet changes, or European policymakers successfully push for enforceable digital sovereignty, the harsh lesson remains: when you run on the cloud, you are renting someone else’s computer, and sometimes that computer is an ocean away. Only real transparency, true regional independence of control services, and strict contractual guarantees will reconcile the power of cloud with the promises of GDPR.

Author’s Note: This article is a technical and legal review based on published AWS statements, industry reporting, and European regulatory analysis. All technical diagrams and system architecture flowcharts are available for reference upon request.