Christian Wenz

Bullet-Proof APIs: The OWASP API Security Top Ten

An attacker changes an ID in the URL and steals another user's data. Learn how to prevent this common and critical API vulnerability.

Bullet-Proof APIs: The OWASP API Security Top Ten
#1about 2 minutes

Understanding the OWASP API Security Top Ten list

The OWASP API Security Top Ten list was created based on public incidents to raise awareness of common vulnerabilities.

#2about 2 minutes

Preventing broken object level authorization vulnerabilities

Attackers can access unauthorized data by guessing sequential IDs if proper permission checks are not implemented for every object.

#3about 5 minutes

Securing APIs against broken authentication flaws

Common authentication risks include misconfigured JWTs and weak secrets, which can be mitigated using the BFF pattern for single page applications.

#4about 3 minutes

Mitigating mass assignment and overposting attacks

Mass assignment vulnerabilities allow attackers to modify protected object properties by sending extra fields in an API request.

#5about 3 minutes

Preventing unrestricted resource consumption and DoS

APIs must implement rate limiting and validate parameters like page size to prevent denial-of-service attacks from excessive resource requests.

#6about 1 minute

Enforcing broken function level authorization

Authorization checks must be applied consistently across all API functions and HTTP methods to prevent unauthorized actions.

#7about 1 minute

Protecting sensitive business flows from API abuse

APIs can be exploited to manipulate business logic, requiring both technical and process-based countermeasures to protect core operations.

#8about 2 minutes

Understanding server side request forgery (SSRF)

An attacker can exploit an SSRF vulnerability to force a server to make requests to internal network resources that are otherwise inaccessible.

#9about 3 minutes

Avoiding security misconfigurations with HTTP headers

Proper configuration, including setting security-enhancing HTTP headers and removing revealing headers, is crucial for securing APIs.

#10about 1 minute

The importance of proper API inventory management

Failing to track all API versions and environments can lead to unmaintained and vulnerable endpoints that pose a significant security risk.

#11about 1 minute

Defending against unsafe consumption of third-party APIs

Treat data from third-party APIs with zero trust, validating and handling it as carefully as any other user input to build resilient applications.

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