Companies House Security Issue

You may have seen (or will soon see) news about a security vulnerability at Companies House. It sounds dramatic, and to be fair, it is, but this is one of those situations where a quick check now can save a much bigger headache later.

So before you assume it’s “just another news story”, it’s worth taking a couple of minutes to make sure everything looks as it should.

What actually happened?

A flaw in the Companies House WebFiling system, dating back to around October 2025, meant that a logged-in user could access another company’s private dashboard without the correct authentication code.

Even more concerning, this didn’t require any technical skill.

In simple terms… it could be done using the back button in a web browser.

Yes, really.

This meant someone could potentially:

• View private director information

• Access sensitive company data

• Make changes to company records

• Even submit filings

The issue was identified on Friday 13 March (unlucky timing…), the service was temporarily shut down, and then restored on Monday 16 March after a fix was applied.

What information could have been exposed?

Potentially affected data includes:

• Directors’ home addresses

• Full dates of birth

• Email addresses

• Company contact details

And in some cases, the ability to:

• Appoint or remove directors

• Change company details

• Submit filings

At the moment, there are no confirmed reports of misuse, but the issue was live for several months, so it’s sensible to double-check.

Important: Our systems (and yours) are still secure

We want to reassure you that:

• This issue was limited to Companies House’s own WebFiling system

• It does not affect the software we use

• All filings we submit through our systems remain secure and unaffected

So this isn’t a breach of our systems or your data with us, it’s specifically about what may have been visible or changeable within Companies House itself.

Why you should still check (even if you’re low-risk)

We know most of our clients aren’t exactly high-profile targets.

But this wasn’t targeted; it was a system flaw that made access too easy.

So the risk isn’t that someone picked you… it’s that they could have landed on your company by accident (or curiosity).

What we’d like you to do first

Before reaching out to us, we recommend a quick check yourself:

• Log in to Companies House WebFiling

• Review your company details and filing history

• Check everything looks exactly as expected

• Look out for anything unfamiliar (especially changes to directors or filings)

It should only take a few minutes, and in most cases, everything will be absolutely fine.

When to come to us

If anything doesn’t look right or if you’d just like peace of mind, we’re here to help.

We are:

• Monitoring the situation closely

• Keeping up to date with any developments

• Ready to support with corrections or reporting issues

Think of us as your last line of defence (and calm heads if anything looks odd).

Our view

There’s no need to panic, but this is definitely one of those moments where a quick check is worthwhile.

So grab a coffee, log in, have a look, and if everything’s fine, you can forget all about it. If not, you know where we are.