CVE-2019-15583 in Community Edition
Summary
by MITRE
An information disclosure exists in < 12.3.2, < 12.2.6, and < 12.1.12 for GitLab Community Edition (CE) and Enterprise Edition (EE). When an issue was moved to a public project from a private one, the associated private labels and the private project namespace would be disclosed through the GitLab API.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 03/26/2024
This vulnerability represents a critical information disclosure flaw in GitLab CE and EE versions prior to 12.3.2, 12.2.6, and 12.1.12 respectively. The issue stems from insufficient access control mechanisms within the GitLab API when handling project transitions from private to public states. When users moved issues between projects with different visibility levels, the system failed to properly sanitize metadata associated with the transferred items, resulting in unauthorized exposure of sensitive information. This flaw specifically affected the handling of private labels and private project namespaces that were attached to issues during the migration process.
The technical implementation of this vulnerability demonstrates a failure in proper privilege escalation checking and data sanitization procedures within GitLab's API endpoints. When an issue was moved from a private project to a public project, the system should have stripped all private metadata including labels and namespace information before making the data accessible through public API endpoints. However, the code path responsible for processing these transitions did not adequately validate or filter the associated metadata, allowing private labels and project namespaces to persist in the public-facing API responses. This represents a classic case of inadequate input validation and insufficient access control enforcement, which aligns with CWE-200 (Information Exposure) and CWE-284 (Improper Access Control) classifications.
The operational impact of this vulnerability is significant for organizations relying on GitLab for version control and issue tracking. Attackers could exploit this flaw to gain unauthorized access to private project information including sensitive labels that might contain confidential project metadata, development status indicators, or internal categorizations that should remain private. The disclosure of private project namespaces particularly impacts organizations with multiple private projects or those using namespace-based access control, as it could reveal the existence and structure of private repositories. This vulnerability directly violates the principle of least privilege and could enable reconnaissance activities for more sophisticated attacks, potentially leading to further exploitation opportunities as outlined in the MITRE ATT&CK framework under T1068 (Exploitation for Privilege Escalation) and T1566 (Phishing for Information).
Organizations should immediately upgrade to GitLab versions 12.3.2, 12.2.6, or 12.1.12 depending on their current installation to remediate this vulnerability. The patch implemented by GitLab addresses the core issue by introducing proper access control checks during project transition operations and ensuring that all private metadata is stripped when moving issues between projects with different visibility levels. Additional mitigations include implementing network-level firewalls to restrict API access, monitoring API logs for unusual access patterns, and conducting regular security audits of project visibility settings. Security teams should also consider implementing automated scanning tools to detect any potential unauthorized information disclosure in their GitLab instances, as this vulnerability could be leveraged in combination with other reconnaissance techniques to build comprehensive attack profiles against development environments.