A missing authentication enforcement vulnerability exists in the mutual TLS (mTLS) implementation used by System REST APIs and SOAP services in multiple WSO2 products. Due to improper validation of client certificate–based authentication in certain default configurations, the affected components may permit unauthenticated requests even when mTLS is enabled. This condition occurs when relying on the default mTLS settings for System REST APIs or when the mTLS authenticator is enabled for SOAP services, causing these interfaces to accept requests without enforcing additional authentication.
Successful exploitation allows a malicious actor with network access to the affected endpoints to gain administrative privileges and perform unauthorized operations. The vulnerability is exploitable only when the impacted mTLS flows are enabled and accessible in a given deployment. Other certificate-based authentication mechanisms such as Mutual TLS OAuth client authentication and X.509 login flows are not affected, and APIs served through the API Gateway of WSO2 API Manager remain unaffected.
Weakness
The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.
Potential Mitigations
- Divide the software into anonymous, normal, privileged, and administrative areas. Identify which of these areas require a proven user identity, and use a centralized authentication capability.
- Identify all potential communication channels, or other means of interaction with the software, to ensure that all channels are appropriately protected, including those channels that are assumed to be accessible only by authorized parties. Developers sometimes perform authentication at the primary channel, but open up a secondary channel that is assumed to be private. For example, a login mechanism may be listening on one network port, but after successful authentication, it may open up a second port where it waits for the connection, but avoids authentication because it assumes that only the authenticated party will connect to the port.
- In general, if the software or protocol allows a single session or user state to persist across multiple connections or channels, authentication and appropriate credential management need to be used throughout.
- Where possible, avoid implementing custom, “grow-your-own” authentication routines and consider using authentication capabilities as provided by the surrounding framework, operating system, or environment. These capabilities may avoid common weaknesses that are unique to authentication; support automatic auditing and tracking; and make it easier to provide a clear separation between authentication tasks and authorization tasks.
- In environments such as the World Wide Web, the line between authentication and authorization is sometimes blurred. If custom authentication routines are required instead of those provided by the server, then these routines must be applied to every single page, since these pages could be requested directly.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
- For example, consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator [REF-45].
References