CVE-2020-2195 in Compact Columns Plugin
Summary
by MITRE
Jenkins Compact Columns Plugin 1.11 and earlier displays the unprocessed job description in tooltips, resulting in a stored cross-site scripting vulnerability that can be exploited by users with Job/Configure permission.
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Analysis
by VulDB Data Team • 06/04/2020
The vulnerability identified as CVE-2020-2195 affects the Jenkins Compact Columns Plugin version 1.11 and earlier, presenting a critical stored cross-site scripting flaw that enables malicious actors to execute arbitrary code within the context of a victim's browser. This vulnerability specifically manifests when the plugin displays unprocessed job descriptions in tooltips, creating an environment where attacker-controlled content can be injected and subsequently rendered without proper sanitization. The security risk is particularly concerning because it requires only minimal privileges, specifically the Job/Configure permission, which is commonly granted to developers and team members who need to manage build configurations. This low privilege requirement significantly expands the potential attack surface and makes the vulnerability more exploitable within typical Jenkins environments where such permissions are frequently distributed.
The technical flaw stems from the plugin's failure to properly sanitize user input before rendering it in tooltip contexts. When administrators or developers configure job descriptions, the Compact Columns Plugin directly incorporates this user-supplied content into tooltip HTML without appropriate encoding or filtering mechanisms. This stored XSS vulnerability allows attackers to inject malicious scripts that persist in the system and execute whenever the tooltip is displayed. The vulnerability is classified under CWE-79 as a Cross-Site Scripting flaw, specifically manifesting as a stored XSS variant where the malicious payload is saved on the server and executed against other users who view the affected tooltips. The attack vector leverages the plugin's tooltip functionality, which is commonly used to provide additional context about jobs, making it a natural target for exploitation.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to perform a wide range of malicious activities within the Jenkins environment. Successful exploitation could allow attackers to steal session cookies, redirect users to malicious sites, modify job configurations, or even escalate privileges within the Jenkins instance. The stored nature of the vulnerability means that once an attacker successfully injects malicious content, it will persist and affect all users who encounter the tooltip, creating a continuous threat vector. This vulnerability particularly affects organizations that rely heavily on Jenkins for continuous integration and deployment processes, where job descriptions often contain sensitive information and where attackers could leverage the XSS to gain unauthorized access to build systems, potentially compromising the entire CI/CD pipeline.
Organizations should immediately upgrade to Jenkins Compact Columns Plugin version 1.12 or later, which contains the necessary patches to address the stored XSS vulnerability. System administrators should implement comprehensive input validation and output encoding mechanisms to prevent similar issues in other plugins or custom code. The mitigation strategy should include regular security assessments of all installed Jenkins plugins, implementing proper privilege management to limit who can configure jobs, and conducting security training for developers who work with Jenkins environments. Additionally, organizations should consider implementing web application firewalls and content security policies as additional defensive measures to protect against XSS attacks. The vulnerability demonstrates the critical importance of proper input sanitization in web applications and highlights the need for continuous security monitoring of third-party plugins in enterprise environments where Jenkins serves as a core infrastructure component. This case underscores the necessity of following security best practices such as those outlined in the OWASP Top Ten and ATT&CK framework, particularly focusing on prevention of XSS vulnerabilities through proper data validation and sanitization techniques.