What is the recent security problem with Companies House data?

Recently, it was discovered that a security flaw in the Companies House system may have allowed logged-in users to view or edit other firms' records.

How should businesses affected by the security problem respond?

If your business may have been affected, it is recommended that you review your details on Companies House to confirm that they are accurate and have not been changed without authorisation.

What type of information may have been exposed due to this security issue?

Details such as directors' home addresses, dates of birth, and email addresses may have been exposed, which can create real-world risks if accessed by the wrong person.

What is the bigger lesson to be learned from this security problem?

The bigger lesson is that digital systems handling legal identity and corporate records need strong controls, as the consequences of failure can be significant. It is important for businesses to regularly review their information on Companies House to ensure its accuracy and integrity.

Firms urged to check if their Companies House data was edited by others

CREATED BY ALISON MEAD

Published: 23/03/2026 @ 09:01AM

#CompaniesHouse #SecurityProblem #Logged-InUsers #ChangeOtherFirmsRecords

I recently read about a serious Companies House security problem that may have let logged-in users see or even change other firms' records. If you're one of the businesses affected, it makes sense to review your details now ...

Edited their data, On Companies House platform, Accurate records

I've been following this Companies House issue closely since the story broke, and it's hard not to see it as a reminder that even central government systems can have weak spots. In this case, I've suggested to my Bookkeeping Buddies that they recommend their own clients review records after a security problem that may have let some users view or edit data on Companies House without authorisation.

What makes this especially uncomfortable is
the kind of information involved!

We're not talking about harmless administrative notes here; details such as directors' home addresses, dates of birth and email addresses may have been exposed. That is exactly the sort of information that can create real-world risk if it lands in the wrong hands, which is why any business should treat this as more than a routine IT hiccup.

From what has been shared so far, the flaw appeared after a change to the WebFiling system, and it was reportedly discovered by an external user who spotted that she could jump into another company's dashboard.

Once that happened, the wider concern became obvious: if one person could navigate into someone else's account space, then the boundary between records was not holding properly. In plain terms, the platform may have allowed edited data to be seen on Companies House by the wrong person.

I think the sensible response is to be methodical rather than panicked. Check who has access, confirm that your registered email address is correct, and look over your filings for anything unusual.

If a company has been changed unexpectedly, that is the point to raise it immediately, because the earlier a problem is spotted, the easier it is to contain. A security problem like this is not just about stolen information; it is also about trust in the integrity of company records.

Companies House said it moved quickly once the issue was
identified and that passwords were not compromised!

That's helpful, but it doesn't remove the need for caution. Even if no files were altered in every case, the possibility that some edited data on Companies House could have been viewed or touched by the wrong user is enough to justify careful checking by every firm that relies on the service.

For me, the bigger lesson is simple: digital systems that handle legal identity and corporate records need exceptionally strong controls, because the consequences of failure are outsized. If you run a business, don't assume the official register is automatically flawless.

Take a few minutes, review what's there, and verify that nobody has edited data on Companies House in a way they shouldn't have.

Until next time ...

ALISON MEAD
I'm your Bookkeeping Buddy: Discover more by clicking here!

Would you like to know more?

If anything I've written in this blog post resonates with you and you'd like to discover more about edited their data on Companies House, it may be a great idea to give me a call on 01604 420057 and let's see how I can help you.

Share the blog love ...

Buffer

Facebook

Twitter

#CompaniesHouse #SecurityProblem #Logged-InUsers #ChangeOtherFirmsRecords

About Alison Mead ...

Alison loves bookkeeping and supporting bookkeepers. She has been helping clients to be better bookkeepers in Sage 50 for over 24 years and has been Xero Accredited in accounts and payroll for a number of years too.

She specialises in a very unique hand-holding method of training, helping bookkeepers and business owners to use their accounts software as and when they need support in setting up and producing their invoices, reports and financial information.

Alison combines her role at Silicon Bullet with her Forever Living network marketing businesses and is often to be seen at business networking meetings as she likes to keep busy.

You know what they say: if you want something done well ask a busy person!

More blog posts for you to enjoy ...

		Building A Bookkeeping Business: Increasing Your Prices You may have already done the difficult part of starting your own bookkeeping business; you've found clients, you've decided on your pricing, and now you're getting on with the day-to-day of looking after the clients you've ....
		Getting your sole trader clients ready for MTD For Income Tax If you're a bookkeeper supporting sole trader clients, you've likely already started receiving questions about Making Tax Digital (MTD) for Income Tax. While the changes may seem daunting at first, they're really about encour...
		Some great reviews for my Bookkeeping Buddy subscription Do It Yourself bookkeeping often feels like a chore when you're managing your own business accounts or even just starting off as a bookkeeper. This is why I created my Bookkeeping Buddy subscription and I'm getting some great...
		Xero pricing update from 1st September 2026 As bookkeepers, we are often the first port of call when clients hear about software price increases. If you've started hearing questions about Xero's latest pricing changes, now is a great opportunity to demonstrate your val...
		Why Should You Use A Bookkeeper? Keeping track of your accounts is a science as well as an art form. Yes, of course you can do it yourself, but wouldn't a bookkeeper make your life a whole lot easier? Having a clear picture of your finances at any given time...
		Bookkeepers: how you can prepare your landlord clients for Making Tax Digital Making Tax Digital (MTD) for Income Tax is no longer a future consideration for landlords. The rollout is now underway, and many landlords will need to change how they keep records and report income to HMRC ......
		Bookkeepers: About the summer 2026 temporary VAT reduction to 5% For many bookkeepers, managing VAT changes can feel like a full-time job, especially when temporary measures are introduced at short notice. The government's announced summer VAT reduction to 5% is one such change, and it is ...
		HMRC's new 55p mileage rate highlights the importance of good bookkeeping HMRC's move to raise the Approved Mileage Allowance Payment (AMAP) rate to 55p per mile is good news for many business owners and employees. As fuel, insurance, servicing, and vehicle costs continue to rise, this update offer...

Other bloggers you may like ...

		From idea to publication: How sBlogIt! creates your content for you Posted by Steffi Lewis on https://www.sblogit.com If blogging continues to fall further down your to-do list, you're not alone. Running a business always demands priority, and turning ideas into consi ...
		The art of outsourcing your visibility so you can get on with running your business Posted by Jacky Sherman on https://www.jackysherman.com After years of working as a coach, mentor, and referral marketing specialist, one of the most common conversations I've had with my clients has been a ...
		Serviced accommodation for contractors in Milton Keynes Posted by Emily Freeman on https://blog.shortstay-mk.co.uk Finding the right serviced accommodation in Milton Keynes can make all the difference to a successful project. Whether you're on a short-term contract ...
		How to deliver a great presentation at an interview Posted by Dave Cordle on https://blog.davecordle.co.uk Before you step into an interview, it's worth remembering that if you've been asked to deliver a presentation, you've already achieved something impor ...

Firms urged to check if their Companies House data was edited by others

What makes this especially uncomfortable isthe kind of information involved!

Once that happened, the wider concern became obvious: if one person could navigate into someone else's account space, then the boundary between records was not holding properly. In plain terms, the platform may have allowed edited data to be seen on Companies House by the wrong person.

Companies House said it moved quickly once the issue wasidentified and that passwords were not compromised!

What makes this especially uncomfortable is
the kind of information involved!

Companies House said it moved quickly once the issue was
identified and that passwords were not compromised!