For a short window over the weekend, the UK’s official company register had to shut down part of its online filing system after a security flaw allowed users to view and alter information belonging to other companies.
Companies House confirmed that its WebFiling service was taken offline at 1.30pm on Friday, 13 March and restored at 9am on Monday, 16 March. The shutdown followed the discovery of a vulnerability that allowed a logged-in user to access elements of another company’s filing account.
According to the official statement, personal and company data such as directors’ dates of birth, residential addresses and company email addresses may have been accessible to other WebFiling users. Companies House also warned that someone could have submitted filings on behalf of another company while the flaw was active.
That includes documents such as company accounts or changes to director details. Those filings would appear on the affected company’s public record if submitted through the system.
The agency said the issue was investigated, fixed and then independently tested before the system went back online.
Andy King, Chief Executive of Companies House, said the organisation moved quickly once the issue was identified and temporarily closed the service while engineers worked on the fix. The agency said it is reviewing whether any records were altered during the period and will contact affected companies if irregular activity is found.
The incident arrives at a time when Companies House is gaining new responsibilities under the Economic Crime and Corporate Transparency Act. The reforms expand the registrar’s role in verifying company data and tackling misuse of the UK corporate register.
Legal experts say the timing increases the importance of maintaining confidence in the system. James Orloff, corporate and commercial partner at London law firm Spector Constant & Williams, said the incident will worry businesses that rely on the register to maintain accurate company information.
“The security issue affecting the Companies House WebFiling service will concern many companies and their officers who rely on the platform to keep their statutory records accurate,” Orloff said. “Confidence in the system matters even more now as Companies House takes on a larger role under the ECCTA reforms.”
He added that the reported weakness could have allowed unauthorised filings, including accounts submissions or director changes, to appear on another company’s record.
“Businesses should follow the guidance issued by Companies House and review their registered details and filing history to confirm that everything on their record is correct,” he said.
Companies House has urged organisations to log in and review their filings to confirm that no unexpected changes were submitted during the affected period.
The agency said further updates will be published if its investigation finds evidence that company records were modified without permission.
