CVE-2020-13343 in GitLab
Summary
by MITRE • 10/06/2020
An issue has been discovered in GitLab affecting all versions starting from 11.2. Unauthorized Users Can View Custom Project Template
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Analysis
by VulDB Data Team • 11/16/2020
The vulnerability identified as CVE-2020-13343 represents a critical access control flaw in GitLab's project template system that has persisted across multiple versions since the release of GitLab 11.2. This security weakness allows unauthorized users to access custom project templates that should only be available to authorized personnel within specific project contexts. The flaw exists in the authorization mechanisms that govern template visibility and access permissions, creating a pathway for malicious actors to bypass intended security boundaries. Such a vulnerability undermines the fundamental principle of least privilege that should govern access to sensitive project artifacts and configurations within GitLab's collaborative development environment.
The technical implementation of this vulnerability stems from inadequate validation of user permissions when accessing project templates within GitLab's code repository management system. Specifically, the authorization checks fail to properly verify whether a user possesses the necessary privileges to view custom templates, particularly when these templates are associated with projects that the user should not have access to. This weakness can be exploited through direct API calls or web interface interactions that retrieve template data without proper access validation. The flaw manifests when the system does not adequately cross-reference user roles, project memberships, and template ownership permissions before granting access to template content. This type of vulnerability aligns with CWE-285, which addresses insufficient authorization in software systems where access controls are improperly implemented or bypassed.
The operational impact of CVE-2020-13343 extends beyond simple information disclosure, as it potentially enables unauthorized users to gain insights into project configurations, development practices, and organizational structures that should remain confidential. Attackers could leverage this vulnerability to gather intelligence about target organizations' development workflows, code patterns, and project dependencies. In enterprise environments where GitLab serves as a central hub for source code management and collaboration, this access could facilitate more sophisticated attacks such as social engineering campaigns or targeted exploitation of project-specific vulnerabilities. The implications are particularly severe for organizations that utilize custom project templates to store sensitive configuration data, build scripts, or proprietary development methodologies that could provide attackers with valuable information for further compromise.
Organizations should implement immediate mitigations including upgrading to GitLab versions that contain the patched authorization controls, typically those released after the vulnerability disclosure. System administrators should conduct comprehensive audits of project template permissions and review existing access controls to ensure that custom templates are properly restricted to authorized users. The implementation of network segmentation and monitoring solutions can help detect unauthorized access attempts to template resources. Additionally, organizations should consider implementing role-based access controls that enforce stricter boundaries around template visibility and ensure that only users with appropriate project-level permissions can access custom templates. This vulnerability demonstrates the importance of maintaining current security practices and regularly reviewing access control mechanisms within collaborative development platforms, as highlighted by ATT&CK technique T1566 which addresses credential access through unauthorized access to system resources.