CVE-2019-16539 in Support Core Plugin
Summary
by MITRE
A missing permission check in Jenkins Support Core Plugin 2.63 and earlier allows attackers with Overall/Read permission to delete support bundles.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 11/22/2019
The vulnerability identified as CVE-2019-16539 represents a critical authorization flaw within the Jenkins Support Core Plugin ecosystem. This issue affects versions 2.63 and earlier, where a fundamental permission validation mechanism has been omitted or incorrectly implemented. The flaw specifically targets the deletion functionality of support bundles, which are essential diagnostic artifacts used for troubleshooting and support purposes within Jenkins environments. These support bundles typically contain sensitive configuration data, build history, and system information that administrators rely upon for operational integrity.
The technical nature of this vulnerability stems from a missing permission check that should have validated whether an authenticated user possesses sufficient privileges to perform destructive operations on support bundles. In properly secured systems, the deletion of support bundles should require elevated permissions beyond basic read access, typically involving administrative or specific support bundle management privileges. The absence of this validation creates a privilege escalation vector where users with merely Overall/Read permission can execute destructive actions that should be restricted to authorized personnel only.
From an operational impact perspective, this vulnerability poses significant risks to Jenkins environments that rely on support bundles for troubleshooting and maintenance activities. Attackers who gain access to systems with read permissions can exploit this flaw to delete critical diagnostic information, potentially disrupting support operations and making it difficult for administrators to diagnose system issues. The deletion of support bundles can also interfere with audit trails and compliance requirements, particularly in regulated environments where maintaining detailed system logs and diagnostic information is mandatory. This vulnerability essentially undermines the principle of least privilege by allowing unauthorized deletion of system artifacts that are crucial for operational continuity.
The vulnerability aligns with CWE-284, which specifically addresses improper access control mechanisms, and demonstrates how inadequate permission validation can lead to privilege escalation scenarios. From an ATT&CK framework perspective, this represents a privilege escalation technique that leverages insufficient authorization checks to gain access to additional system capabilities. Organizations implementing Jenkins as part of their CI/CD pipelines may find this vulnerability particularly concerning as it could be exploited by attackers who have gained initial access through other means to escalate their privileges and disrupt critical build and deployment processes.
Mitigation strategies for this vulnerability require immediate action including upgrading to Jenkins Support Core Plugin version 2.64 or later where the permission check has been properly implemented. System administrators should also review and audit existing user permissions to ensure that read-only access is not inadvertently granted to users who should only have basic viewing capabilities. Additionally, organizations should implement monitoring solutions to track support bundle deletion activities and establish alerting mechanisms for unauthorized access attempts. Regular security assessments of Jenkins plugins and configurations should be conducted to identify similar permission validation gaps that could potentially exist in other components of the Jenkins ecosystem.