CVE-2017-2610 in Jenkins
Summary
by MITRE
jenkins before versions 2.44, 2.32.2 is vulnerable to a persisted cross-site scripting in search suggestions due to improperly escaping users with less-than and greater-than characters in their names (SECURITY-388).
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 03/13/2023
The vulnerability identified as CVE-2017-2610 affects Jenkins continuous integration and delivery platform versions prior to 2.44 and 2.32.2, representing a critical security flaw in the search functionality that enables persistent cross-site scripting attacks. This issue stems from inadequate input validation and output escaping mechanisms within Jenkins' search suggestions feature, specifically when processing user names containing special characters that can be interpreted as HTML markup by web browsers. The vulnerability was documented under SECURITY-388 and demonstrates a classic weakness in web application security where user-provided data is not properly sanitized before being rendered in web pages. The affected Jenkins versions fail to adequately escape less-than and greater-than characters in user names, allowing malicious actors to inject malicious scripts that persist across sessions and can be executed whenever the affected search suggestions are displayed.
The technical implementation of this vulnerability exploits the fundamental principle that user input should never be directly rendered in web contexts without proper sanitization. When Jenkins processes search suggestions for users whose names contain characters such as < or >, these characters are not properly escaped or encoded before being included in the HTML output. This creates an environment where an attacker can craft user names containing embedded script tags or other malicious payloads that execute in the context of other users' browsers. The persistence aspect of this vulnerability means that once a malicious user name is created and stored in Jenkins, the associated script will execute every time the search suggestions are displayed, making it particularly dangerous in multi-user environments where administrators and developers regularly interact with the system. This flaw directly aligns with CWE-79, which describes cross-site scripting vulnerabilities where untrusted data is improperly incorporated into web pages, and represents a failure in the principle of least privilege where user input is treated as trusted content.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to escalate privileges, steal session cookies, perform actions on behalf of other users, and potentially gain access to sensitive build artifacts, credentials, and system configurations. In enterprise environments where Jenkins serves as a central automation platform, this vulnerability could allow adversaries to compromise the entire continuous integration pipeline, affecting code deployment processes, access to source code repositories, and potentially leading to supply chain attacks. The attack vector is particularly concerning because it requires minimal user interaction beyond creating a malicious user account or manipulating existing user data, making it an attractive target for both internal and external threat actors. The vulnerability also demonstrates weaknesses in Jenkins' input validation processes and highlights the importance of comprehensive security testing across all application components, particularly those handling user-generated content in web interfaces. Organizations using affected Jenkins versions face significant risk of unauthorized access and data compromise, particularly in environments where Jenkins is used for building and deploying critical applications.
Mitigation strategies for CVE-2017-2610 require immediate patching of Jenkins installations to versions 2.44 or 2.32.2, which contain the necessary fixes for proper input escaping and output encoding in search suggestions. Administrators should also implement additional security measures including input validation for user names, regular security audits of user accounts, and monitoring for suspicious user account creation patterns. The fix implemented in the patched versions addresses the root cause by ensuring that all user names containing special characters are properly escaped before being rendered in search suggestions, preventing the injection of malicious HTML or JavaScript code. Organizations should also consider implementing web application firewalls to detect and block potential XSS attempts, and establish secure coding practices for all Jenkins plugins and custom integrations. This vulnerability serves as a reminder of the critical importance of input sanitization and output encoding in web applications, and aligns with ATT&CK technique T1059.001 for command and scripting interpreter, as attackers could potentially leverage this vulnerability to execute malicious commands through script injection. Regular security updates and vulnerability assessments should be implemented as part of comprehensive security management processes to prevent similar issues from affecting Jenkins installations in production environments.