Companies House Security Issue

On Friday 13 March, Companies House identified an issue with WebFiling. They took the service offline at 1:30pm that day while they investigated and fixed the issue. The service was back online at 9am on Monday 16 March.

Companies House report that the issue arose from a system update in October 2025 and was not the result of a malicious attempt to attack our systems. It was not a cyber-attack. They state the issue could only have been exploited by a logged-in user performing a specific set of actions.

Companies House reported this on a precautionary basis to make people aware.

They had no confirmed reports of any data having been accessed or changed without permission and believe the issue could not have been used to extract data in large volumes.

However, as a precaution, they request that directors check company registered details and filing history to make sure everything looks correct.

For more information see an issue with WebFiling