CVE-2022-34208 in Beaker Builder Plugin
Summary
by MITRE • 06/23/2022
A missing permission check in Jenkins Beaker builder Plugin 1.10 and earlier allows attackers with Overall/Read permission to connect to an attacker-specified URL.
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Analysis
by VulDB Data Team • 07/14/2022
The vulnerability identified as CVE-2022-34208 resides within the Jenkins Beaker builder plugin version 1.10 and earlier, representing a critical authorization bypass issue that fundamentally undermines the security model of the Jenkins continuous integration platform. This flaw manifests as a missing permission check that allows unprivileged users to exploit a functionality that should be restricted to authorized personnel. The vulnerability specifically affects systems where the Beaker builder plugin is installed and configured, creating an attack surface that can be leveraged by threat actors with minimal privileges to execute potentially harmful actions against the targeted infrastructure.
The technical implementation of this vulnerability stems from inadequate access control validation within the plugin's codebase, where the system fails to properly verify user permissions before allowing network connectivity operations. An attacker with only Overall/Read permission, which is typically considered a low-privilege access level, can manipulate the plugin to establish connections to arbitrary URLs specified by the attacker. This represents a classic case of insufficient authorization checks where the system assumes that legitimate users will not attempt to abuse functionality, failing to implement proper validation mechanisms that would normally be enforced by the Jenkins security framework.
The operational impact of this vulnerability extends beyond simple information disclosure, as it enables attackers to potentially exfiltrate sensitive data, establish command and control channels, or perform reconnaissance activities against internal systems that the Jenkins server can access. The ability to connect to attacker-specified URLs means that malicious actors can leverage this vulnerability to redirect traffic to malicious servers, harvest credentials from internal services, or use the Jenkins server as a pivot point for further attacks within the network infrastructure. This vulnerability particularly impacts organizations that rely heavily on Jenkins for automated build processes and have configured the Beaker builder plugin as part of their CI/CD pipeline.
Organizations should immediately upgrade to a patched version of the Jenkins Beaker builder plugin to remediate this vulnerability, as the affected versions lack proper access control validation mechanisms. The recommended mitigation strategy involves implementing network segmentation to restrict outbound connections from Jenkins servers, monitoring for unusual network activity that might indicate exploitation attempts, and conducting thorough access control reviews to ensure that users have appropriate privilege levels. Additionally, implementing Jenkins security best practices such as role-based access control, regular security audits, and network monitoring solutions can help detect and prevent exploitation attempts. This vulnerability aligns with CWE-693, which covers protection mechanism failures, and could be categorized under ATT&CK technique T1071.004 for application layer protocol: DNS, as attackers might use this vulnerability to establish DNS-based command and control channels. Organizations should also consider implementing Jenkins security configurations that enforce stricter access controls and regularly validate that all plugins are running with the minimum necessary privileges to perform their intended functions.