Published: 08/06/2022

How to protect your API against excessive data exposure

Application programming interfaces (APIs) are vital for many businesses — but they’re also a significant security risk. APIs are a prime target for cybercriminals looking to exploit vulnerabilities to steal data or attack your network. But by overexposing your own API data, you can also cause privacy breaches.

Excessive data exposure is one of the top three API security concerns. But your API needs to expose some data in order to function properly. So how can you avoid overexposing your API data, while allowing it to interact effectively with external parties?

What is an API and how does it work?

APIs allow external systems to interact and exchange data with your application. They enable programs to request services and information from your server via an API call, which then serves users the information they’ve requested.

There are three main types of API:

  • Open APIs — these can be accessed by anyone
  • Partner APIs — developers can make these available to selected external business partners via a public portal
  • Internal APIs — these APIs can only be accessed by approved developers via a private portal.

APIs are widely used across all kinds of sectors, including financial services, retail, telecommunications, and medical services. They store huge volumes of sensitive data — which makes them a prime target for attackers.

Broken or unsecured APIs are a significant security risk, as they contain flaws and vulnerabilities that are easy for criminals to exploit. But even functioning APIs can be a goldmine for hackers if they expose potentially sensitive data.

Public vs private APIs

Public and private APIs are usually used in different ways — so switching to a private API isn’t always the answer. Public APIs are designed to allow genuine developers to build new applications using the data stored in your API. This adds value to your system since it opens your product or service up to new markets and users with minimal effort on your part.

Private APIs give your internal developers and approved partners easy access to the backend of your application. They can improve productivity by automating processes, minimizing coding issues, and providing valuable insights to your technology team.

Because they can be accessed by anyone, public or open APIs are a much bigger security risk than private APIs. However, data exposure can happen in both — so you need to reduce the chances of your API responses offering access to unnecessary information.

Why does excessive data exposure occur?

Excessive data exposure happens when your API response provides more information than is necessary to fulfill a user’s request. Hackers can discover critical vulnerabilities like this and exploit them to gain unfiltered access to sensitive data stored in your API.

Breaches usually occur when administrators allow access to unfiltered data in the API, whether unwittingly or as an intentional shortcut.

The risks of exposing API data to third parties

Exposing too much data is a huge risk to your business for many reasons. It can cause:

  • Identity theft and fraud — your staff and customers may be vulnerable to crimes that can cause financial and emotional distress
  • Privacy and data breach fines — revealing personally identifiable information in breach of privacy protection laws like CCPA and GDPR can incur penalties worth millions of dollars
  • Loss of sales — customers who no longer trust you with their data can withdraw business, causing a significant decline in sales and revenue
  • Increased overheads — your team will need to work round the clock to minimize the damage caused by data breaches, costing staff time and money.

A record-breaking 1,862 data breaches occurred in 2021. Hackers and cybercriminals are constantly looking for API security flaws to exploit — so you need the best possible protection for your public or private API.

How to protect yourself from excessive API data exposure

There are a few ways to minimize sensitive data exposure, and secure your API data against intrusive bots and hackers:

  1. Encrypt all data

If your data is encrypted, hackers are less likely to be able to decode and use it even if they gain access to your API. Use strong encryption methods like SSL and FTPS to keep your data private even if your API security is breached.

  1. Only request and store the data you need

API hackers can’t steal data if you don’t store it. Minimize the amount of personal data you store in your API by only requesting the exact information you need, and only storing it for as long as you need to.

  1. Don’t allow unfiltered data access for any reason

Allowing developers to filter sensitive data can be a fast way to allow them to return the API responses they need — but it’s also a quick way to expose excessive data. Ensure you have specific, restricted API responses in place for the most common API requests you receive.

  1. Protect your API with automated bot management

Detect malicious bots before they infiltrate your API with an automated bot management system. Netacea’s technology identifies and blocks all kinds of sophisticated bots, protecting your API from exposing data to malicious sources.

If you’re concerned about the security of your API, learn how bot management can protect your data and give you immediate protection against automated attacks on your API.

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