Companies House Glitch Exposes Data of 5 Million Companies

A vulnerability in the Companies House website allowed unauthorized access to the dashboards of over five million registered companies, exposing sensitive information such as directors' addresses and email addresses. Discovered by John Hewitt from Ghost Mail on March 13, 2026, the flaw enabled users to edit company details and potentially file fraudulent accounts. The exploit required no technical hacking; users could simply log in and manipulate the system by pressing the 'back' button to access other companies' dashboards. Companies House temporarily shut down its online filing service in response to the incident. Security experts have raised concerns about the implications for GDPR compliance and the potential for fraud. The exact duration the vulnerability was active remains unclear, but it poses significant risks if exploited. Companies House has acknowledged the issue and is investigating the breach.

Key Points: • A vulnerability exposed sensitive data of over five million companies. • Users could access and edit other companies' information without hacking. • Companies House has temporarily shut down its online filing service.