CVE-2015-5305 in OpenShift Enterprise
Summary
by MITRE
Directory traversal vulnerability in Kubernetes, as used in Red Hat OpenShift Enterprise 3.0, allows attackers to write to arbitrary files via a crafted object type name, which is not properly handled before passing it to etcd.
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Analysis
by VulDB Data Team • 06/26/2022
The vulnerability identified as CVE-2015-5305 represents a critical directory traversal flaw within the Kubernetes container orchestration platform that was subsequently impacting Red Hat OpenShift Enterprise 3.0. This weakness stems from insufficient input validation mechanisms within the system's object handling processes, specifically when processing object type names that are submitted to the etcd distributed key-value store. The flaw creates a path traversal condition that enables malicious actors to manipulate file system access patterns through crafted object identifiers, potentially leading to unauthorized file system modifications and system compromise.
The technical implementation of this vulnerability occurs at the interface between Kubernetes' API layer and the etcd storage backend where object type names are processed without adequate sanitization or validation. When an attacker submits a maliciously crafted object type name containing directory traversal sequences such as "../", the system fails to properly sanitize these inputs before forwarding them to etcd. This inadequate input handling creates an opportunity for attackers to manipulate the file system paths used by etcd, potentially allowing them to write files to arbitrary locations within the system's file hierarchy. The vulnerability is classified under CWE-22 as a directory traversal attack, which is a well-established class of security flaws that has been consistently documented in security frameworks and standards.
The operational impact of this vulnerability extends beyond simple file system manipulation to encompass potential system compromise and data integrity breaches. Attackers could leverage this weakness to write malicious files to critical system directories, potentially leading to privilege escalation, persistent backdoors, or the corruption of essential system components. The vulnerability affects the core storage and retrieval mechanisms of Kubernetes, which means that successful exploitation could compromise the entire container orchestration environment. Given that OpenShift Enterprise 3.0 was designed for enterprise deployment scenarios, this vulnerability presents a significant risk to organizations relying on containerized applications and microservices architectures. The attack surface is particularly concerning because etcd serves as a critical component for maintaining cluster state and configuration data, making any compromise of its integrity potentially catastrophic for cluster operations.
Mitigation strategies for CVE-2015-5305 should focus on implementing robust input validation and sanitization mechanisms within the Kubernetes API layer before any object type names are processed or forwarded to etcd. Organizations should ensure that all object identifiers are properly validated against established naming conventions and that directory traversal sequences are explicitly rejected. The implementation of proper access controls and privilege separation between the API layer and etcd components can significantly reduce the impact of such vulnerabilities. Additionally, regular security updates and patches should be applied to ensure that known vulnerabilities are addressed promptly. Security monitoring should be enhanced to detect anomalous patterns in object creation and modification activities that might indicate exploitation attempts. Organizations should also consider implementing network segmentation and firewall rules to limit direct access to etcd endpoints, reducing the attack surface available to potential adversaries. The vulnerability highlights the importance of following secure coding practices and input validation methodologies as outlined in industry standards such as the OWASP Top Ten and NIST cybersecurity frameworks, emphasizing the need for comprehensive security controls throughout the software development lifecycle.