CVE-2017-1000403 in Speaks! Plugin
Summary
by MITRE
Jenkins Speaks! Plugin, all current versions, allows users with Job/Configure permission to run arbitrary Groovy code inside the Jenkins JVM, effectively elevating privileges to Overall/Run Scripts.
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Analysis
by VulDB Data Team • 07/16/2020
The vulnerability identified as CVE-2017-1000403 affects the Jenkins Speaks! plugin, a widely used component that enables Jenkins to communicate with various messaging systems including Slack, HipChat, and other chat platforms. This security flaw exists in all current versions of the plugin and represents a critical privilege escalation vulnerability that allows attackers to execute arbitrary Groovy code within the Jenkins Java Virtual Machine environment. The vulnerability stems from insufficient input validation and sanitization within the plugin's code execution mechanisms, creating an avenue for malicious users to bypass normal access controls and gain elevated privileges.
The technical implementation of this vulnerability occurs through the plugin's handling of user-provided parameters that are subsequently processed as Groovy script code within the Jenkins JVM context. When users with merely Job/Configure permissions attempt to configure jobs that utilize the Speaks! plugin, the plugin fails to properly validate or sanitize the input parameters, allowing attackers to inject malicious Groovy code that gets executed with the privileges of the Jenkins master process. This flaw directly violates the principle of least privilege and creates a path for attackers to escalate their access from basic job configuration rights to full script execution capabilities across the entire Jenkins instance.
The operational impact of this vulnerability is severe and far-reaching within Jenkins environments. An attacker exploiting this vulnerability can execute arbitrary code with the highest privileges available to the Jenkins master, potentially leading to complete system compromise. The privilege escalation allows malicious actors to access all Jenkins jobs, view sensitive configuration data, extract credentials stored in Jenkins, modify build processes, and potentially pivot to other systems within the network. This vulnerability particularly affects continuous integration/continuous deployment environments where Jenkins serves as a central automation hub, making it a prime target for attackers seeking persistent access to development infrastructure.
Security professionals should implement immediate mitigations including disabling the affected plugin until a patched version is available, restricting access to the Speaks! plugin configuration interface, and implementing network segmentation to limit the impact of potential exploitation. Organizations should also conduct comprehensive audits of their Jenkins configurations to identify all instances of the plugin and ensure proper access controls are in place. The vulnerability aligns with CWE-94, which describes the weakness of executing arbitrary code, and maps to ATT&CK technique T1059.007 for executing commands through Groovy scripting, highlighting the need for robust input validation and privilege separation measures. Additionally, this vulnerability demonstrates the importance of securing plugin ecosystems in enterprise automation platforms, as third-party components often represent significant attack surface areas that require careful monitoring and validation.