CVE-2022-2227 in Community Edition
Summary
by MITRE • 07/01/2022
Improper access control in the runner jobs API in GitLab CE/EE affecting all versions prior to 14.10.5, 15.0 prior to 15.0.4, and 15.1 prior to 15.1.1 allows a previous maintainer of a project with a specific runner to access job and project meta data under certain conditions
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Analysis
by VulDB Data Team • 07/18/2022
This vulnerability represents a critical access control flaw in GitLab's runner jobs API that undermines the integrity of project permissions and data confidentiality. The issue stems from insufficient validation mechanisms that allow former project maintainers to retain access to sensitive job and project metadata even after their access rights have been revoked. This weakness exists across multiple GitLab versions including 14.10.4 and earlier, 15.0.3 and earlier, and 15.1.0 and earlier releases, making it a widespread concern affecting organizations relying on GitLab's CI/CD infrastructure. The vulnerability specifically targets the runner jobs API endpoint where project maintainers who previously had access to a project can exploit a gap in the access control system to retrieve information about jobs and project metadata that should no longer be accessible to them.
The technical implementation of this flaw involves a failure in the permission validation logic within GitLab's API handling layer. When a user's role is changed from maintainer to a lower privilege level or when they are removed from a project entirely, the system should invalidate any cached access tokens or session data related to runner jobs. However, the vulnerability allows for continued access through specific conditions that maintain the previous maintainer's authorization context. This typically occurs when the system fails to properly invalidate the runner job access tokens or when the API endpoint does not correctly verify current project membership status before returning sensitive data. The flaw operates at the application layer and can be exploited by an authenticated user who maintains knowledge of the target project's runner configuration.
The operational impact of this vulnerability extends beyond simple data exposure to potentially enable more sophisticated attacks within the CI/CD pipeline environment. Former maintainers with continued access can obtain detailed information about job execution parameters, build artifacts, environment variables, and project configurations that could be leveraged for privilege escalation or lateral movement within the development infrastructure. This access could reveal sensitive information such as database connection strings, API keys, or other credentials stored in job environments that are typically protected from unauthorized access. Organizations using GitLab for continuous integration and deployment workflows face particular risk since this vulnerability could allow attackers to gain insights into automated build processes and potentially compromise the integrity of their software delivery pipeline. The vulnerability also impacts audit and compliance requirements as it creates unauthorized access paths that could go undetected in security monitoring systems.
Organizations should immediately update their GitLab installations to the patched versions including 14.10.5, 15.0.4, and 15.1.1 to remediate this vulnerability. The patch addresses the access control validation by implementing proper session invalidation mechanisms and ensuring that API endpoints correctly verify current project membership status before returning sensitive data. System administrators should also review and audit existing project memberships to ensure that former maintainers have been properly removed from projects where they no longer require access. Security monitoring should be enhanced to detect unusual API access patterns from former maintainers, and organizations should consider implementing additional access controls for runner jobs that limit data exposure based on role-based access control principles. This vulnerability aligns with CWE-284 which addresses improper access control in software systems, and could be categorized under ATT&CK technique T1548.1 for privilege escalation through abuse of credentials, representing a significant risk to CI/CD pipeline security and overall software development infrastructure integrity.