This disclosure policy applies only to vulnerabilities in Office for National Statistics (ONS) products and services under the following conditions:

  • “In scope” vulnerabilities must be original, previously unreported, and not already discovered by internal procedures.

  • Volumetric vulnerabilities are not in scope; this means that simply overwhelming a service with a high volume of requests is not in scope.

  • Reports of non-exploitable vulnerabilities, or reports indicating that our services do not fully align with “best practice” (for example missing security headers) are not in scope.

  • TLS configuration weaknesses, for example “weak” cipher suite support or the presence of TLS 1.0 support, are not in scope.

This policy applies to everyone, including ONS staff, third party suppliers and general users of ONS public services.


If you have discovered something you think is an in-scope security vulnerability (as listed in the Scope section), you can submit a report. In your submission, include:

  • details of the website or page where the vulnerability can be seen
  • a brief description of the type of vulnerability, for example, “an XSS vulnerability”

Your report should provide objective, non-destructive proof of exploitation. This helps to ensure that the report can be assessed quickly and accurately. It also reduces the likelihood of duplicate reports or malicious exploitation of some vulnerabilities, such as subdomain takeovers.

What to expect

After you have submitted your report, we will respond to it within five working days and aim to assess your report within 10 working days. We will keep you informed about our progress via HackerOne if you have registered for an account.

Priority for bug fixes or mitigations is assessed by looking at how complicated they are and how serious the consequences might be. Vulnerability reports might take some time to assess and address. You are welcome to enquire on the status of the process but should avoid doing so more than once every 14 days. This will allow our teams to focus on the reports.

When the reported vulnerability is resolved, or remediation work is scheduled, the Vulnerability Disclosure Team will notify you and invite you to confirm that the solution covers the vulnerability adequately.


This policy is designed to be compatible with common vulnerability disclosure good practice. It does not give you permission to act in any manner that is inconsistent with the law, or that might cause the Office for National Statistics (ONS) to be in breach of any of its legal obligations, including but not limited to:

  • The Computer Misuse Act (1990)
  • The General Data Protection Regulation 2016/679 (GDPR) and the Data Protection Act 2018
  • The Copyright, Designs and Patents Act (1988)
  • The Official Secrets Act (1989)

The ONS will not seek prosecution of any security researcher who reports any security vulnerability in an ONS service or system where the researcher has acted in good faith and in accordance with this disclosure policy.


You must not:

  • access unnecessary amounts of data; two or three records are enough to demonstrate most vulnerabilities, such as an enumeration or direct object reference vulnerability
  • use high-intensity invasive or destructive technical security scanning tools to find vulnerabilities
  • violate the privacy of ONS users, staff, contractors, services or systems, for example, by sharing, redistributing and/or not properly securing data retrieved from our systems or services
  • communicate any vulnerabilities or associated details using methods not described in this policy
  • modify data in any ONS systems or services
  • disrupt any ONS services or systems
  • socially engineer, “phish”, or physically attack ONS staff or infrastructure

You must also not disclose any vulnerabilities in ONS systems or services to third parties or the public before the ONS has confirmed that those vulnerabilities have been mitigated or rectified; this is not intended to stop you notifying a vulnerability to third parties for whom the vulnerability is directly relevant. An example would be where the vulnerability being reported is in a third-party software library or framework. Details of the specific vulnerability as it applies to the ONS must not be referenced in such reports.