CVE-2015-7536 in Jenkins
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in CloudBees Jenkins before 1.640 and LTS before 1.625.2 allows remote authenticated users to inject arbitrary web script or HTML via unspecified vectors related to workspaces and archived artifacts.
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Analysis
by VulDB Data Team • 07/06/2022
The CVE-2015-7536 vulnerability represents a critical cross-site scripting flaw affecting CloudBees Jenkins versions prior to 1.640 and LTS versions before 1.625.2. This vulnerability resides within the web application's handling of workspace and archived artifact data, creating an attack surface where authenticated users can potentially execute malicious scripts against other users within the same Jenkins environment. The flaw stems from insufficient input validation and output encoding mechanisms that fail to properly sanitize user-supplied data before rendering it in web contexts, allowing attackers to inject malicious HTML or JavaScript code that executes in the browsers of other users.
The technical implementation of this vulnerability involves the improper handling of user-controllable parameters within Jenkins' workspace and archived artifact presentation layers. When authenticated users interact with these components, the application fails to adequately escape or encode special characters in user-provided content, creating opportunities for XSS exploitation. Attackers can leverage this weakness by crafting malicious inputs that, when processed and displayed by the application, execute unintended code within the victim's browser context. This particular vulnerability is classified under CWE-79 as "Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')", which is a fundamental web security weakness that has been consistently ranked among the top ten web application security risks by OWASP.
From an operational perspective, this vulnerability poses significant risks to Jenkins environments where multiple users collaborate on shared projects. The authenticated nature of the attack means that an attacker must first gain valid credentials, but once inside the system, they can potentially compromise other users' sessions and access sensitive project data. The impact extends beyond simple script execution as attackers could potentially steal session cookies, redirect users to malicious sites, or perform actions on behalf of victims within the Jenkins environment. The vulnerability affects not just individual users but entire development teams and organizations that rely on Jenkins for continuous integration and deployment processes, potentially disrupting workflows and exposing confidential build artifacts or source code.
The exploitation of this vulnerability aligns with several ATT&CK techniques including T1059.007 for "Command and Scripting Interpreter: JavaScript" and T1566.001 for "Phishing: Spearphishing Attachment". Organizations should implement immediate mitigations including applying the security patches released by CloudBees for Jenkins versions 1.640 and LTS 1.625.2, implementing proper input validation and output encoding mechanisms, and conducting regular security assessments of their Jenkins installations. Additionally, network segmentation and privilege separation can help limit the potential impact of successful exploitation, while monitoring for unusual user activities and automated script injections can provide early detection capabilities. The vulnerability serves as a reminder of the critical importance of maintaining up-to-date software versions and implementing comprehensive security controls in development environments where sensitive operational data is processed and stored.