CVE-2017-1000402 in Swarm Plugin Client
Summary
by MITRE
Jenkins Swarm Plugin Client 3.4 and earlier bundled a version of the commons-httpclient library with the vulnerability CVE-2012-6153 that incorrectly verified SSL certificates, making it susceptible to man-in-the-middle attacks.
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Analysis
by VulDB Data Team • 07/16/2020
The Jenkins Swarm Plugin Client vulnerability CVE-2017-1000402 represents a critical security flaw that emerged from the inclusion of an outdated and vulnerable library component within the plugin's distribution. This particular vulnerability stems from the bundling of commons-httpclient library version 3.1, which contained a fundamental flaw in its SSL certificate validation mechanism that had been previously identified and documented in CVE-2012-6153. The issue manifests when the plugin establishes secure connections to Jenkins masters, creating a pathway for attackers to exploit the weakened SSL verification process and potentially intercept or manipulate communications between the swarm client and the server infrastructure.
The technical flaw within the commons-httpclient library operates through a specific weakness in its SSL certificate validation routine where the library fails to properly verify the hostname against the certificate presented during the SSL handshake process. This vulnerability falls under the CWE-295 category of "Improper Certificate Validation" and specifically relates to CWE-310, which addresses "Cryptographic Issues" in the context of SSL/TLS implementation flaws. When the Jenkins Swarm Plugin Client attempts to establish a secure connection using this vulnerable library, it accepts SSL certificates that do not properly match the target host, effectively allowing attackers to present fraudulent certificates that would be accepted by the client. This weakness directly enables man-in-the-middle attack scenarios where an adversary positioned between the client and server can intercept, modify, or redirect communications without detection.
The operational impact of this vulnerability extends beyond simple network monitoring capabilities, as it fundamentally compromises the integrity and confidentiality of communications within Jenkins environments that utilize the Swarm Plugin. Attackers exploiting this vulnerability can perform various malicious activities including credential theft, unauthorized access to build artifacts, code injection attacks, and complete compromise of the build infrastructure. The vulnerability affects all versions of the Jenkins Swarm Plugin Client prior to version 3.5, making it a widespread concern for organizations that have not updated their Jenkins installations. This issue particularly affects continuous integration and deployment environments where automated build processes and secure communication channels are essential for maintaining software supply chain integrity. The vulnerability creates a persistent risk that remains active until the affected plugin is updated to incorporate a patched version of the commons-httpclient library or the vulnerable component is removed from the distribution.
Organizations should implement immediate mitigation strategies including updating the Jenkins Swarm Plugin Client to version 3.5 or later, which contains the patched commons-httpclient library that properly validates SSL certificates. System administrators should also consider implementing network-level monitoring to detect unusual SSL certificate behavior and establish automated patch management processes to prevent similar vulnerabilities from being introduced through third-party components. The remediation process should include comprehensive inventory checks to identify all systems utilizing the vulnerable plugin and ensure that the update process does not introduce compatibility issues with existing Jenkins configurations. Additionally, organizations should review their overall security posture and consider implementing additional layers of protection such as certificate pinning, network segmentation, and regular security audits to prevent similar vulnerabilities from affecting their infrastructure. This vulnerability demonstrates the critical importance of maintaining up-to-date dependencies and the potential risks associated with using outdated libraries that may contain known security flaws, particularly in environments where automated build and deployment processes rely heavily on secure communication channels.