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Data protection testing

GDPR Penetration Testing

GDPR does not hand you a checklist of controls. Article 32 asks for appropriate technical and organizational measures to secure personal data, judged against the state of the art and the risk. A penetration test is how you demonstrate that judgement in practice: independent evidence that you actively look for the flaws that would expose personal data, and fix them.

This engagement focuses on exactly those flaws, on the systems that hold personal data, and produces documentation that supports your accountability obligations if a regulator ever asks what you did to protect it.

Why GDPR accountability calls for penetration testing

Article 32 requires appropriate security measures and, importantly, a process for regularly testing and evaluating their effectiveness. A penetration test is the most direct way to satisfy the testing-and-evaluating part, and the accountability principle means you must be able to show what you did, not merely assert that you are secure.

The financial stakes are unusually high. GDPR penalties reach into the tens of millions of euros or a percentage of global turnover, and regulators weigh the technical measures you had in place when deciding on a fine after a breach. A documented programme of independent testing is strong evidence of diligence.

Most GDPR-relevant breaches come down to personal data being accessible to the wrong person: a broken access-control flaw, an exposed database, an API returning more than it should. These are precisely the issues a penetration test is designed to surface before an attacker or a curious user finds them.

What we test

Access control over personal data

Whether users can reach personal data belonging to others by manipulating identifiers or bypassing authorization, the most common route to a reportable breach.

Data exposure and minimization

APIs and pages that return more personal data than necessary, and personal data leaking into logs, URLs, error messages, or third-party requests.

Authentication and account security

Login, password reset, and session handling, since account takeover is a direct compromise of the affected person's data.

Encryption and transport

Personal data transmitted or stored without appropriate encryption, which weighs directly on the Article 32 assessment.

The report you receive

The report supports your accountability obligations and guides remediation. It contains:

  • An executive summary framed around personal-data risk for your DPO and leadership.
  • A methodology statement referencing OWASP testing standards.
  • Findings rated by severity with reproduction steps, data-exposure impact, and remediation.
  • Notes on how findings relate to the Article 32 security-of-processing obligations.
  • A retest and updated report evidencing that risks were addressed.

Findings we commonly report in this category

Personal data exposure via IDOR

An endpoint that returns another person's profile, order, or message when an id is changed, a textbook GDPR-reportable exposure.

Excessive data in API responses

Endpoints returning fields the client never uses, contradicting data minimization and widening exposure if intercepted.

Personal data in logs and third-party calls

Identifiers or sensitive fields leaking into analytics, logs, or referrer headers where they were never meant to go.

Account takeover paths

Weak password reset or session handling that lets an attacker seize an account and, with it, all the personal data inside.

Frequently asked questions

Does GDPR require a penetration test?

Not by name, but Article 32 requires appropriate technical measures and a process for regularly testing and evaluating their effectiveness. A penetration test is the standard way to meet the testing obligation and to evidence accountability if a regulator asks.

How does a penetration test help after a data breach?

Regulators consider the technical measures you had in place when deciding on enforcement. A documented programme of independent testing, with a remediation trail, is strong evidence that you took security seriously, which can materially affect the outcome.

What counts as personal data for the test?

Anything that identifies a person, directly or indirectly: names, emails, identifiers, location, and more. We focus testing on the systems and endpoints that handle this data, since that is where GDPR risk concentrates.

How often should we test for GDPR?

At least annually and after significant changes to systems handling personal data. GDPR frames it as regular testing, so a consistent cadence with documentation is what demonstrates compliance.

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