In an increasingly connected world, APIs (Application Programming Interfaces) are the backbone of digital services, enabling apps, platforms, and partners to exchange data. But while innovation moves quickly, API security often lags dangerously behind.
According to Raidiam’s API Security Report, 84% of surveyed organizations are exposing sensitive data via weak API security practices. This article explores both bad and good API security examples, including a real-world data breach, to help teams recognize red flags and adopt secure architectures.
→ Check out next: API Security Report: Helping Enterprises Recognize and Address Critical Risks
Here are some imaginary - but realistic - bad practices seen all too often in the wild.
A retail API uses a hardcoded API key to authorize mobile apps. The key:
Attackers reverse-engineer the mobile app, extract the key, and use it to modify other users’ orders.
Why this is bad: Static keys are often leaked and over-privileged. Without scope or expiration, one compromised key can lead to mass data exposure.
A logistics platform exposes a vehicle-tracking API without any rate limits. Anyone with an API key can send unlimited queries.
Impact:
A competitor scripts calls to scrape data on fleet movements, pricing patterns, and delivery routes — gaining an unfair edge.
Why this is bad: Without throttling, APIs become sitting ducks for scraping, abuse, and brute-force attacks.
→ Related article: The API Security Gap: Why Most Enterprises Are Still Vulnerable
A fintech startup allows third-party providers (TPPs) to access its APIs using only basic OAuth 2.0 client authentication methods such as client_secret_post or client_secret_basic, without enforcing stronger forms of client authentication like private_key_jwt or mutual TLS (mtls).
Why this is bad: Client secrets are part of a symmetric authentication approach - simply put, they must be known to both the resource owner and the client, and are exchanged as part of the authentication process. This leaves open multiple avenues of interception / exposure.
Additionally, as no certificates are involved, access tokens cannot be bound, and are open to interception and replay by unauthorized parties.
One of the most illustrative real-world API security failures is the Dell customer data breach.
An attacker posed as a fake partner and gained access to a public API endpoint that revealed full customer records using just a service tag (ID).
Takeaway: Even one weak API — without proper validation, monitoring, or access control — can compromise millions of users.
Source: Salt Security Review of Dell Breach
Related read: Why API Security Vulnerabilities Should Keep You Up at Night
Now let’s look at what great API security looks like, using a financial-grade setup based on OpenID FAPI (Financial-grade API) and mTLS.
A regulated Open Banking API in the UK requires:
Why this is excellent: mTLS and FAPI enforce cryptographic identity, mitigate replay attacks, and align with Zero Trust architecture.
As noted in Raidiam’s research:
“Only one organization surveyed had implemented a full modern security profile… and it was operating under an Open Banking regime.”
— API Security Report, 2025
→ Related read: The Leaders Are Already Securing APIs with FAPI + mTLS
Use these principles to upgrade your API security strategy:
Resources like JARM and API Gateway policies can also strengthen runtime protection and trust validation.
As the Raidiam survey highlights, most organizations fall into the “Act Urgently” category — especially those outside regulated environments. With APIs now a primary attack surface, the stakes are high.
Forward-looking teams should:
Download the full API Security Report from Raidiam to explore the critical risks, real-world breaches, and proven solutions shaping modern API security.
This essential report includes:
👉 Don’t wait for a breach — get the insights now and start hardening your APIs today.