CVE-2017-1000104 in Jenkins
Summary
by MITRE
The Config File Provider Plugin is used to centrally manage configuration files that often include secrets, such as passwords. Users with only Overall/Read access to Jenkins were able to access URLs directly that allowed viewing these files. Access to view these files now requires sufficient permissions to configure the provided files, view the configuration of the folder in which the configuration files are defined, or have Job/Configure permissions to a job able to use these files.
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Analysis
by VulDB Data Team • 11/22/2019
The Config File Provider Plugin for Jenkins represents a critical access control vulnerability that fundamentally undermined the security posture of organizations relying on centralized configuration management. This vulnerability existed within Jenkins' permission model where users with minimal Overall/Read access could bypass intended security boundaries to access sensitive configuration files containing secrets such as passwords, API keys, and other confidential information. The flaw stemmed from insufficient authorization checks within the plugin's URL handling mechanisms, allowing unauthorized access to configuration file contents through direct URL requests. The vulnerability directly violated the principle of least privilege by enabling read access to sensitive data without proper authorization validation, creating a significant attack surface for malicious actors seeking to extract confidential information from Jenkins environments.
The technical implementation of this vulnerability exploited Jenkins' permission system by failing to enforce proper access controls on specific URL endpoints within the Config File Provider Plugin. When users with Overall/Read permissions attempted to access configuration files through direct URL paths, the system did not properly validate whether the requesting user possessed sufficient privileges to view the specific configuration file contents. This occurred because the plugin's code did not implement adequate authorization checks before serving configuration file data, effectively treating all users with basic read access as having unrestricted access to sensitive configuration resources. The flaw was particularly dangerous because configuration files often contained credentials, encryption keys, and other sensitive information that should only be accessible to users with explicit configuration permissions.
The operational impact of this vulnerability extended far beyond simple information disclosure, as it created persistent security risks for organizations managing sensitive infrastructure through Jenkins. Attackers could leverage this vulnerability to extract credentials and secrets from configuration files, potentially gaining access to downstream systems, databases, and cloud resources that relied on those configuration values. The vulnerability's persistence meant that once exploited, attackers could maintain access to sensitive information without requiring additional privileges or complex attack vectors. This posed significant risk to CI/CD pipelines, automated deployment processes, and infrastructure management systems that depend on Jenkins for configuration management. Organizations using the plugin were vulnerable to credential theft, unauthorized system access, and potential data breaches that could compromise entire infrastructure ecosystems.
The remediation for this vulnerability required implementing proper authorization checks within the Config File Provider Plugin to ensure that access to configuration files was restricted based on appropriate Jenkins permissions. Users needed to possess either sufficient permissions to configure the provided files, view the configuration of the folder containing the configuration files, or have Job/Configure permissions to jobs that could utilize these files. This fix aligns with security best practices outlined in the CWE-284 access control weakness category, which specifically addresses insufficient access control mechanisms. The solution also corresponds to ATT&CK technique T1552.001 for credentials in files, as it addressed unauthorized access to sensitive configuration data that could contain credentials and secrets. Organizations should have implemented immediate patching of the plugin, reviewed existing access controls, and conducted security assessments to identify any potential exploitation that may have occurred before the fix was applied.