Every application you put online is an open door with your name on it. The login page, the customer portal, the mobile backend, the public API that partners integrate against -- each one is a piece of software that accepts input from strangers and is expected to behave perfectly under every circumstance, including the ones its developers never imagined. Attackers know this. They probe constantly, automatically, at scale, looking for the one endpoint that validates input a little too trustingly or the one API that returns a little more data than it should.
APIs in particular have become the favourite target. Modern systems are stitched together from services, and the API layer is where the business logic and the sensitive data actually live. A single broken authorisation check -- an endpoint that lets one user request another user's records by changing an ID in the URL -- can quietly expose an entire customer base. These flaws rarely announce themselves. They sit in production, working fine for legitimate users, until someone curious starts iterating through identifiers.
Why Periodic Testing Is Not Enough
The traditional answer is a penetration test once or twice a year and a scanner in the build pipeline. Both are valuable, but both share a fatal limitation: they describe the application as it was at a moment in time. Software ships continuously now. A dependency updated on Tuesday, a new endpoint added on Wednesday, a configuration changed on Thursday -- any of these can open a hole that the last quarterly test never saw. Protecting applications and APIs requires something that lives in production with the running traffic, watching and acting all the time. That is the role Shield plays.
Shield in Brief
Shield is a security product that protects your applications and APIs at runtime. As in every domain it covers, it operates on two layers simultaneously. The passive protection layer delivers continuous monitoring, detection, inline anonymization of sensitive responses and complete audit visibility -- protection that observes and shields without interrupting legitimate traffic. The active protection layer adds real-time enforcement, blocking and intervention that step in the moment an attack or abuse is detected. Shield delivers both layers together, because seeing an attack is only useful if you can also stop it before it succeeds.
Passive Protection: Continuous Runtime Visibility
The passive layer turns your application traffic into something you can actually understand and govern. It watches every request and response without standing in the way:
- Continuous monitoring of live application and API traffic, building an accurate, always-current inventory of every endpoint -- including the forgotten and undocumented ones that scanners miss.
- Detection of attack patterns and abuse: injection attempts, credential stuffing, scraping, anomalous request volumes and broken-authorisation probing, identified by behaviour rather than signatures alone.
- Inline anonymization of sensitive fields in API responses, so that personal data and secrets are masked before they reach a client that does not need them in full -- a safeguard even when an endpoint is over-sharing.
- Audit and visibility that records who called what, with which token, from where, and with what result -- the forensic trail you need to investigate an incident and demonstrate GDPR compliance.
None of this changes how your application behaves for genuine users. Latency stays low and traffic flows normally; the passive layer simply makes the invisible visible and quietly shields sensitive output.
Active Protection: Stopping the Attack Mid-Request
Knowing an attack is underway is not the same as surviving it. The active layer enforces in real time, on the request, before damage is done:
- Blocking malicious requests inline -- an injection payload, an exploit attempt against a known weakness, a request that violates the API's intended contract -- so the harmful call never reaches your code.
- Real-time intervention such as rate-limiting an abusive client, challenging suspicious sessions, and cutting off a token that is being used to enumerate records.
- Automated response when an attack pattern escalates: tightening rules for the offending source, isolating an endpoint under active exploitation, and alerting the security team immediately.
- Virtual patching that lets you neutralise a newly disclosed vulnerability at the Shield layer within minutes, buying your developers time to ship a proper fix without leaving the door open in the meantime.
Passive protection gives you a continuous, honest picture of how your applications and APIs are actually being used and attacked. Active protection lets you shut an attack down while the request is still in flight. Shield runs both at once, so a probe is not just logged -- the exploit behind it is stopped.
Security That Keeps Pace with Delivery
The pace of modern software is the core challenge: you ship faster than you can audit. Shield resolves that tension by moving protection into the runtime, where it keeps up with every release automatically. The passive layer ensures a new endpoint is seen the moment it goes live, and the active layer ensures it is defended from the first request -- not from the next quarterly test. The result is application and API security that is continuous, enforceable, and aligned with how you actually build and deploy, rather than a snapshot that is out of date the moment it is signed.
Want to secure your company's applications?
Find out how Shield's passive and active protection work together to defend your apps and APIs in real time. Get in touch with CREBISO to learn more or request a demo.
Talk to CREBISO →More on Shield
Applications are one layer of your attack surface. The same passive-and-active approach protects the others: