CVE-2014-3665 in Jenkins
Summary
by MITRE
CloudBees Jenkins before 1.587 and LTS before 1.580.1 do not properly ensure trust separation between a master and slaves, which might allow remote attackers to execute arbitrary code on the master by leveraging access to the slave.
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Analysis
by VulDB Data Team • 04/18/2018
The vulnerability identified as CVE-2014-3665 represents a critical trust boundary failure within CloudBees Jenkins continuous integration platform versions prior to 1.587 and LTS versions before 1.580.1. This flaw fundamentally undermines the security architecture designed to isolate master and slave nodes in distributed Jenkins environments, creating a pathway for remote attackers to escalate privileges and execute arbitrary code on the master node. The issue stems from insufficient validation mechanisms that should normally enforce strict separation between the master and slave components, which are intended to operate in distinct security contexts with different privilege levels and access controls.
The technical implementation of this vulnerability allows attackers with access to a slave node to exploit the trust relationship between master and slave systems. In normal Jenkins operations, the master node orchestrates builds and manages the overall environment while slave nodes execute specific tasks in isolated environments. However, this vulnerability enables attackers to leverage their access to a slave system to bypass these security boundaries and gain unauthorized access to the master node's execution environment. The flaw specifically relates to the improper handling of serialized objects and remote procedure calls that traverse between slave and master components, allowing malicious payloads to be executed with master-level privileges.
The operational impact of CVE-2014-3665 is severe and multifaceted, potentially enabling complete system compromise and unauthorized access to sensitive data and infrastructure. Attackers who gain access to any slave node in the Jenkins environment can use this vulnerability to execute arbitrary code on the master node, which typically holds administrative privileges and can access all build configurations, credentials, and project data. This compromise extends beyond simple code execution to include potential lateral movement within the network, as the master node often has access to additional systems and resources. The vulnerability is particularly dangerous in enterprise environments where Jenkins masters typically manage critical build processes and contain sensitive authentication information.
This vulnerability maps directly to CWE-284 (Improper Access Control) and CWE-502 (Deserialization of Untrusted Data) within the Common Weakness Enumeration framework, reflecting both the access control failure and the unsafe deserialization practices that enable the exploit. From the MITRE ATT&CK framework perspective, this vulnerability aligns with techniques such as privilege escalation and command and control communications, as attackers can use the compromised slave to establish persistent access to the master node. The attack vector requires minimal privileges initially, as attackers only need access to a single slave node to initiate the exploitation process, making this particularly dangerous in environments where multiple slave nodes are accessible to different user groups or where slave node access is less strictly controlled than master node access. Organizations should implement immediate mitigations including upgrading to patched versions of Jenkins, implementing network segmentation between master and slave nodes, and conducting thorough security audits of their Jenkins configurations to ensure proper isolation between components.