Report a vulnerability on an FCDO system
Source: gov.uk (2025-11-13)

Guidance on how to report a security vulnerability on any Foreign, Commonwealth, and Development Office service or system.

Introduction

Foreign, Commonwealth, and Development Office leads the UK’s diplomatic, development and consular work around the world. We have a vital purpose to:
- safeguard the UK’s national security by countering terrorism and weapons proliferation, and working to reduce conflict
- build the UK’s prosperity by increasing exports and investment, opening markets, ensuring access to resources, and promoting sustainable global growth
- support British nationals around the world through modern and efficient consular services
Read more about what we do on GOV.UK (https://www.gov.uk/government/organisations/foreign-commonwealth-development-office/about)

This vulnerability disclosure policy applies to any vulnerabilities you are considering reporting to us (the “Organisation”). We recommend reading this vulnerability disclosure policy fully before you report a vulnerability and always acting in compliance with it. We value those who take the time and effort to report security vulnerabilities according to this policy. However, we do not offer monetary rewards for vulnerability disclosures.

Reporting

If you believe you have found a security vulnerability, submit your report to us (https://hackerone.com/ac818ab4-dcc1-4f5b-99f6-57df1614f1b9/embedded_submissions/new?locale=en).

In your report please include details of:
- the website, IP or page where the vulnerability can be observed
- a brief description of the type of vulnerability, for example,“XSS vulnerability”
- steps to reproduce – these should be a benign, non-destructive, proof of concept. This helps to ensure that the report can be triaged quickly and accurately. It also reduces the likelihood of duplicate reports, or malicious exploitation of some vulnerabilities, such as sub-domain takeovers
What to expect

After you have submitted your report, we will respond to your report within 5 working days and aim to triage your report within 10 working days. We’ll also aim to keep you informed of our progress.

Priority for remediation is assessed by looking at the impact, severity and exploit complexity. Vulnerability reports might take some time to triage or address. You are welcome to enquire on the status but should avoid doing so more than once every 14 days. This allows our teams to focus on the remediation.

We will notify you when the reported vulnerability is remediated, and you may be invited to confirm that the solution covers the vulnerability adequately.

Once your vulnerability has been resolved, we welcome requests to disclose your report. We’d like to unify guidance to affected users, so please do continue to coordinate public release with us.

Guidance

You must not:
- break any applicable law or regulations
- access unnecessary, excessive or significant amounts of data
- modify data in the Organisation’s systems or services
- use high-intensity invasive or destructive scanning tools to find vulnerabilities
- attempt or report any form of denial of service, e.g. overwhelming a service with a high volume of requests
- disrupt the Organisation’s services or systems
- submit reports detailing non-exploitable vulnerabilities, or reports indicating that the services do not fully align with “best practice”, for example missing security headers
- submit reports detailing TLS configuration weaknesses, for example “weak” cipher suite support or the presence of TLS1.0 support
- communicate any vulnerabilities or associated details other than by means described in the published security.txt
- social engineer, ‘phish’ or physically attack the Organisation’s staff or infrastructure
- demand financial compensation in order to disclose any vulnerabilities
You must:
- always comply with data protection rules and must not violate the privacy of the Organisation’s users, staff, contractors, services or systems. You must not, for example, share, redistribute or fail to properly secure data retrieved from the systems or services.
- securely delete all data retrieved during your research as soon as it is no longer required or within 1 month of the vulnerability being resolved, whichever occurs first (or as otherwise required by data protection law)
Legalities

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 which might cause the Organisation or partner organisations to be in breach of any legal obligations.

However, if legal action is initiated by a third party against you and you have complied with this policy, we can take steps to make it known that your actions were conducted in compliance with this policy.