Getting through a PSN IT Health Check (ITHC) can be a bit of a maze. If you've ever been involved in one, you’ll know it’s often filled with uncertainty, a fair bit of stress, and a lot of manual penetration testing. EASM tools, or External Attack Surface Management solutions, aren’t going to tick every box for you on their own. They can’t magically make you compliant. But they can definitely make the whole process a lot more manageable and less chaotic.

Let’s start with the basics. The PSN (Public Services Network) ITHC is a requirement for any organisation connecting to the UK government’s PSN. It's designed to ensure your infrastructure is secure enough to handle sensitive public data. The check itself is usually carried out by a CREST-accredited third party and heavily leans on manual penetration testing. You can’t get away with just automated scans or a fancy report. It’s hands-on, thorough, and sometimes open to interpretation depending on who’s testing you.

That last part’s worth repeating. The PSN ITHC often leaves room for interpretation. Different testers might have different views on what’s acceptable or not. Some are strict, others more pragmatic. One tester might flag something as high risk that another wouldn’t bat an eye at. This makes preparation a bit of a guessing game. And that’s exactly where EASM solutions can lend a hand.

While they’re not built to replace pentests, EASM tools do give you ongoing visibility of your external-facing infrastructure. They help you see what an attacker or a penetration tester would see from the outside. This can include things like open ports, forgotten subdomains, exposed services, expired certificates, and the occasional shadow IT surprise you didn’t even know existed.

In the lead up to a PSN ITHC, having this kind of visibility is gold. You can spot misconfigurations or risky exposures long before your tester does. You can clean up abandoned assets or shut down old services that are still sitting there quietly collecting dust and risk. If anything, EASM acts like a warm-up lap before the real test. It won't carry you across the finish line, but it’ll help you avoid tripping on the way there.

It also makes post-check life easier. The ITHC often comes with a list of issues you need to resolve, usually within a tight timeframe. If you’ve already got an EASM platform running, you can validate those fixes faster. You don’t have to wait for the next retest to know if something’s still exposed. And if you’re running continuous monitoring, you’ll be in a much better position for next year’s test too.

There’s also a cultural benefit. Using an EASM solution helps instil more awareness of external risk across your team. Instead of just bracing for an annual check, you start thinking more like an attacker year-round. And that shift in mindset? It’s something auditors and testers really appreciate.

To sum it all up, no, EASM will not replace the need for manual penetration testing or directly help you pass a PSN ITHC. But it fits incredibly well into the preparation and ongoing compliance cycle. It helps reduce surprises, improve visibility, and move you from reactive to proactive.

‍