CVE-2024-41820 in kubean
Summary
by MITRE • 08/05/2024
Kubean is a cluster lifecycle management toolchain based on kubespray and other cluster LCM engine. The ClusterRole has `*` verbs of `*` resources. If a malicious user can access the worker node which has kubean's deployment, he/she can abuse these excessive permissions to do whatever he/she likes to the whole cluster, resulting in a cluster-level privilege escalation. This issue has been addressed in release version 0.18.0. Users are advised to upgrade. There are no known workarounds for this vulnerability.
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Analysis
by VulDB Data Team • 08/06/2024
The vulnerability identified as CVE-2024-41820 affects Kubean, a cluster lifecycle management toolchain that operates on kubespray and other cluster lifecycle management engines. This toolchain serves as a critical component for managing Kubernetes cluster operations, including deployment, configuration, and maintenance tasks across distributed environments. The security flaw manifests in the form of overly permissive ClusterRole definitions that grant excessive privileges to authenticated users within the cluster environment.
The technical implementation of this vulnerability stems from the ClusterRole configuration that includes wildcard verbs and resources, specifically employing `*` for both verb and resource specifications. This configuration pattern creates a dangerous permission structure where any authenticated user with access to the worker node hosting Kubean's deployment can leverage these broad privileges to execute arbitrary operations across the entire cluster. The ClusterRole's wildcard specification essentially grants full administrative control over all Kubernetes resources and operations, bypassing normal access control mechanisms and privilege boundaries that should normally restrict user capabilities.
The operational impact of this vulnerability represents a severe cluster-level privilege escalation attack vector that can lead to complete cluster compromise. An attacker who gains access to any worker node containing Kubean's deployment can immediately escalate their privileges to cluster administrator level, enabling them to manipulate all cluster resources including pods, services, persistent volumes, and cluster-wide configurations. This vulnerability essentially eliminates the security boundary that should exist between different user roles and cluster components, allowing a single compromised node to potentially provide access to the entire Kubernetes infrastructure. The implications extend beyond simple privilege escalation to include potential data exfiltration, service disruption, and unauthorized access to sensitive cluster operations.
This vulnerability aligns with CWE-276, which describes improper privilege management, and demonstrates characteristics consistent with the ATT&CK technique T1078.004 for Valid Accounts and T1566.001 for Phishing. The security weakness represents a classic case of excessive privilege assignment where the principle of least privilege has been completely ignored in the ClusterRole definition. Organizations using Kubean should immediately upgrade to version 0.18.0 or later to address this issue, as no effective workarounds exist for this particular vulnerability. The lack of available workarounds underscores the critical nature of this flaw and the necessity for immediate remediation through the official software update process. The vulnerability highlights the importance of proper access control configuration and the potential catastrophic consequences that can arise from overly permissive security settings in container orchestration platforms.