CVE-2024-5891 is a vulnerability identified in Red Hat Quay 3, a container image registry platform. The issue arises from weak authentication mechanisms related to OAuth token usage. Specifically, if an attacker can obtain the client ID of an application, they can leverage an OAuth token to authenticate to that application even if they lack access rights to the organization that owns the application. This vulnerability does not affect authorization controls directly; it only impacts authentication. However, in scenarios where applications or endpoints rely solely on authentication without enforcing proper authorization checks, an attacker could gain unauthorized access to resources or services. The vulnerability requires the attacker to have low privileges (PR:L) and does not require user interaction (UI:N), but the attack complexity is high (AC:H), indicating some non-trivial conditions must be met to exploit it. The CVSS v3.1 base score is 4.2, reflecting limited confidentiality and integrity impacts and no availability impact. No known exploits have been reported in the wild. The vulnerability highlights the importance of separating authentication from authorization and ensuring that authorization is enforced independently to prevent unauthorized access even if authentication is bypassed or weakened.

The primary impact of CVE-2024-5891 is unauthorized authentication to applications within Red Hat Quay 3 environments. While the vulnerability does not directly grant authorization, it can lead to unauthorized access if applications rely solely on authentication for access control. This can result in exposure of sensitive container images, metadata, or internal services to unauthorized users. Organizations using Red Hat Quay 3 in their container supply chain or DevOps pipelines may face risks of data leakage or unauthorized manipulation of container images. The impact is limited to confidentiality and integrity, with no direct availability impact. However, the potential for unauthorized access could facilitate further attacks or lateral movement within an environment. Since Red Hat Quay is widely used in enterprise container management, organizations with containerized workloads and DevOps practices are at risk. The medium severity score reflects the need for attention but indicates that exploitation requires specific conditions and is not trivial.

1. Immediately review and update OAuth client ID management practices to ensure client IDs are not exposed or easily obtainable by unauthorized parties. 2. Enforce strict authorization checks on all endpoints and applications, ensuring that authentication alone does not grant access. Implement role-based access control (RBAC) or attribute-based access control (ABAC) mechanisms. 3. Apply the latest patches and updates from Red Hat as they become available to address this vulnerability directly. 4. Audit existing applications and services integrated with Red Hat Quay 3 to verify that they do not rely solely on authentication for access control. 5. Monitor logs and authentication events for unusual OAuth token usage or authentication attempts from unexpected client IDs. 6. Consider implementing additional layers of security such as network segmentation and multi-factor authentication (MFA) where applicable. 7. Educate development and operations teams about the distinction between authentication and authorization to prevent similar misconfigurations.