Broken Object Level Authorization - 2023 OWASP Top 10 API Security Risks

Summary

In this video, the focus is on the critical security vulnerability known as Broken Object Level Authorization (BOLA), ranked as one of the top risks by OWASP. The script explains how this vulnerability allows unauthorized users to access or manipulate resources they shouldn't, using the example of a blogging application where users can potentially modify or delete posts they don't own. The video emphasizes the importance of proper access control mechanisms and suggests implementing well-defined access scopes for resources. Key prevention strategies include validating user permissions before granting access to sensitive data or actions.

Takeaways

• 😀 Broken object-level authorization (BOLA) is a vulnerability where users can access or modify resources they shouldn't be able to.
• 😀 This vulnerability is listed in the OWASP Top Ten, highlighting its significance in application security.
• 😀 BOLA typically occurs when there is a lack of proper access control for objects within an API or server.
• 😀 Resource ownership plays a critical role in determining which users can access or modify specific data in an application.
• 😀 For example, in a blogging application, authors should be able to edit or delete only their own posts, not others'.
• 😀 If BOLA occurs, unauthorized users could bypass access mechanisms to modify or delete data they don't own.
• 😀 While a trivial issue in a blogging app, BOLA is a serious threat in applications handling sensitive data, like banking or medical apps.
• 😀 To prevent BOLA, access controls should define clear scopes for different objects and resources exposed by API endpoints.
• 😀 Implementing validation mechanisms to ensure that access scopes are checked before granting access is crucial for security.
• 😀 Proper access management in APIs can help prevent unauthorized operations and protect sensitive user data from malicious actors.

Q & A

What is broken object level authorization (BOLA)?

BOLA is a vulnerability where a user is able to access, modify, or perform actions on resources they should not have access to, often by bypassing access control mechanisms in an API.

How does broken object level authorization occur?

BOLA occurs when a user can access or perform operations on objects that do not belong to them, due to insufficient or improper access control in an API.

Can you provide an example of broken object level authorization in a blogging application?

In a blogging app, an author can edit or delete their own posts, but with BOLA, a malicious user might be able to access and modify or delete posts that they don't own.

Why is broken object level authorization more critical in sensitive applications like banking or healthcare?

In banking or healthcare, unauthorized access to sensitive data could lead to serious consequences such as financial loss, privacy breaches, or legal repercussions, making BOLA a critical security concern.

What is meant by 'resource ownership' in the context of APIs?

Resource ownership refers to the concept that each resource in an API is owned by a specific user, and access to those resources should be restricted to the owner or those with explicit permission.

What is a suggested preventive measure for broken object level authorization?

A key preventive measure is to define clear access scopes for different objects exposed via API endpoints and to validate these scopes before allowing access to resources.

What role does scope definition play in preventing BOLA?

Scope definition ensures that only authorized users can access specific resources by explicitly defining which users or roles can interact with particular data or perform specific actions.

How can access control mechanisms prevent broken object level authorization?

Access control mechanisms enforce restrictions on who can access or modify resources by validating the user's permissions and ensuring they match the resource ownership before performing operations.

Why is it important to validate scopes before serving resources to the client?

Validating scopes ensures that the user making the request has the proper permissions to access or modify the requested resource, preventing unauthorized actions and protecting sensitive data.

What could happen if broken object level authorization is not properly addressed in an application?

If BOLA is not addressed, unauthorized users could gain access to sensitive data or perform harmful actions such as data deletion or alteration, leading to security breaches and potential financial or legal consequences.