CVE-2020-2323 in Chaos Monkey Plugin
Summary
by MITRE • 12/03/2020
Jenkins Chaos Monkey Plugin 0.4 and earlier does not perform permission checks in an HTTP endpoint, allowing attackers with Overall/Read permission to access the Chaos Monkey page and to see the history of actions.
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Analysis
by VulDB Data Team • 12/12/2020
The Jenkins Chaos Monkey Plugin vulnerability represents a critical authorization bypass flaw that undermines the security model of the Jenkins continuous integration platform. This vulnerability affects versions 0.4 and earlier of the Chaos Monkey plugin, which is designed to introduce controlled chaos into production systems for resilience testing purposes. The plugin's primary function is to simulate various failure scenarios to test system robustness, making its security implications particularly concerning for organizations relying on Jenkins for their automation infrastructure.
The technical flaw manifests in the plugin's HTTP endpoint implementation where proper permission validation is absent or insufficient. Specifically, attackers who possess the Overall/Read permission level can bypass intended access controls to reach the Chaos Monkey administrative interface. This permission level typically grants users the ability to view basic Jenkins information but should not provide access to plugin-specific administrative functions. The vulnerability stems from a lack of proper authentication checks within the plugin's web endpoints, allowing unauthorized access to sensitive operational data through what should be restricted administrative pages.
The operational impact of this vulnerability extends beyond simple information disclosure, as it provides attackers with visibility into the history of chaos actions executed within the system. This historical data may contain sensitive information about system vulnerabilities, failure patterns, and operational weaknesses that could be exploited in subsequent attacks. The exposure of action history could reveal the timing and nature of chaos events, potentially enabling attackers to correlate this information with other system events or to predict future operational patterns. Organizations using this plugin may unknowingly expose their system resilience testing activities, potentially compromising the effectiveness of their chaos engineering initiatives.
From a cybersecurity perspective, this vulnerability aligns with CWE-284, which addresses improper access control, and represents a clear violation of the principle of least privilege. The ATT&CK framework categorizes this as a privilege escalation technique where attackers leverage existing permissions to access restricted functionality. The vulnerability demonstrates how seemingly benign plugins can introduce significant security risks when proper access control mechanisms are not implemented. Organizations implementing chaos engineering practices must ensure that their security tooling does not inadvertently create attack vectors that expose operational information to unauthorized parties.
The recommended mitigations include immediate upgrade to versions of the Chaos Monkey plugin that address this authorization bypass, implementation of network segmentation to limit access to Jenkins instances, and enforcement of more granular permission controls within Jenkins itself. Administrators should also consider implementing additional monitoring and logging around plugin access to detect unauthorized attempts to access administrative interfaces. Regular security assessments of Jenkins plugins and their configurations should be conducted to identify similar authorization gaps. Organizations may also need to review their overall Jenkins security posture, ensuring that all plugins implement proper access control mechanisms and that the principle of least privilege is consistently enforced across all administrative interfaces.