APIs (Application Programming Interfaces) are portals through which different apps, systems, and devices exchange information. APIs allow apps to interact with each other, for example, when you’re on a website and logging in via your Google account or getting real-time weather updates within an app. Because APIs are so important and widely used, they’ve also become a target of choice for hackers. An open API can expose entry points to problems, including divulging user data or landing attackers on networks they shouldn’t be able to breach. API Vulnerability Assessment and Penetration Testing (API VAPT) is thus the highest priority. API VAPT allows businesses to find and fix API problems before cyber attackers do.
In this article, we will discuss 5 popular API vulnerabilities and observe how API VAPT can protect your applications and users from them.
Top 5 API Vulnerabilities Found During VAPT
1. Broken Object Level Authorization (BOLA)
What does it mean:
It is when the API does not check if a user can see some information or perform some action. The attackers can guess or manipulate IDs in the API request and see other individuals’ information.
Example
One common BOLA issue occurs when the user modifies the order ID in the shopping application’s API request chat and sees someone else’s order information.
How API VAPT helps:
- Validation of permission checks to prevent users from asking for something they ought not.
- ID checks are deterministic, i.e., 123, 124, etc.
- This means patches, i.e., using random IDs (UUIDs) and stringent checks on every request.
Explore our complete guide on API Penetration Testing.
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2. Broken Authentication
What does it mean:
Authentication is how apps verify you. Hackers can masquerade as users if authentication is broken, e.g., lacking tokens, weak passwords that can be guessed, or inadequately controlled sessions.
Example
A login system without an action to verify if a token has not expired can be abused by hackers to keep users logged into the app even when they have logged out.
How API VAPT assists:
- Guarantees login and token controls for weak spots.
- Check sessions are timing out as planned, and tokens are processed securely.
- Offers best practice suggestions, i.e., secure token verification and password handling.
3. Excessive Data Exposure
What does it mean:
Sometimes, APIs send more data than needed, even if it’s hidden on the front end. Hackers can still see this data by directly interacting with the API.
Example:
An API provides full user accounts, email accounts, and internal IDs when simple names are requested. Hackers easily notice otherwise concealed information.
How API VAPT benefits:
- It authenticates API responses for extra information.
- Blocks transmitting sensitive information that should not be transmitted.
- Directs developers to transmit only more information, nothing less.
4. No Rate Limiting
What does it mean:
Rate limiting specifies how often one may call APIs. Without rate limiting, attackers might spam the API or perform brute force attacks (e.g., guessing a bunch of passwords).
Example:
An open login API with no rate limiting can result in guessing indefinitely until they’re logged in.
How API VAPT helps:
- Perform stress tests to verify if the API is choking or crashing under heavy load.
- Tries brute force attacks to verify if rate limiting is in place.
- Recommends defenses like request throttling, CAPTCHA, and lockouts.
5. Security-related misconfigurations
What does it mean:
These are random misconfigurations on how the API or the platform it runs is being configured. It could be old software, open debugging output, or accidentally exposing admin panels.
Example
An API “in debug mode” can return error messages to attackers, making the system structure safer to attack.
How API VAPT assists:
- Ensures the misconfiguration of the API environment.
- Verifies stale libraries, open ports, and leaked files.
- Confirms easy-to-understand solutions to issues, like disabling debug mode or security settings.
You might like to explore: API Security Checklist: 15 Must-Follow Steps to Secure Your API.
Why API VAPT Is a Must-Have
A website security scan does not necessarily scan your APIs properly. That’s why API VAPT is unique; it burrows deep into how your APIs function, how data is moving, and where possible vulnerabilities could be hiding, if at all.
Key Benefits
- Timely alert of API vulnerability even before there are actual attacks.
- Good, tailor-made reports for your dev team, with simple step-by-step fixes.
- Constant security through repeated testing as your app grows.
API VAPT in Action: What to Look Out For
This is roughly how it goes:
- Scoping: The professionals already have a good idea of your API — what it is, how it works, and what to investigate.
- Information Gathering: They gather public and concealed information, endpoints, and tokens.
- Testing: Manual testing and automated software, where the tester is trying to exploit the API like an attacker.
- Reporting: There is an explicit report with findings, threats, and solutions in plain words.
- Re-testing: After you’ve plugged the loopholes, the team double-tests to ensure all is safe.
Read our guide to 10 Best Api Security Testing Tools.
Tips to Secure API Tighten (aside from VAPT)
Though VAPT is obligatory, here are some of the things your team will need to do to ensure APIs are secured at all times:
- Use Authentication Everywhere: This includes not only external APIs but also internal APIs.
- Adhere to the Principle of Least Privilege: Grant users and apps the least privileges they need.
- Keep Documents up-to-date so your security team knows what APIs are available and what they’re being used for.
- Don’t Expose Internal APIs.
- Encrypt Data in Transit through HTTPS.
- Audit APIs for suspicious use or traffic patterns.
Have questions about API security or VAPT? Let our experts guide you.
Talk to our Cybersecurity Expert to discuss your specific needs and how we can help your business.
Final thoughts
APIs are now the preferred building block of digital systems, but power is said to be accompanied by responsibility. Making your APIs available to the world for everyone to use is leaving your front door open for hackers to enter.
With awareness of most API vulnerabilities, i.e., broken authentication, data exposure, and rate-limiting vulnerability, you can take action on them in a way that you can fix them. And with API VAPT, you can get expert guidance in identifying these vulnerabilities before the malicious ones can exploit them.
It’s not so much about preventing breaches as it is about winning your users’ confidence, being data protection law compliant, and having smooth runs on your systems.
Need API VAPT services?
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