CVE-2025-47885 is a high-severity stored cross-site scripting (XSS) vulnerability found in the Jenkins Health Advisor by CloudBees Plugin, specifically in versions 374.v194b_d4f0c8c8 and earlier. This plugin is part of the Jenkins Project, a widely used open-source automation server for continuous integration and continuous delivery (CI/CD). The vulnerability arises because the plugin does not properly escape responses received from the Jenkins Health Advisor server. Consequently, if an attacker can control or manipulate the server responses, they can inject malicious scripts that are stored and later executed in the context of the Jenkins web interface. This stored XSS flaw allows attackers to execute arbitrary JavaScript code in the browsers of users who access the affected Jenkins instance, potentially leading to session hijacking, credential theft, unauthorized actions, or further compromise of the Jenkins environment. The CVSS 3.1 base score of 8.8 reflects the critical impact on confidentiality, integrity, and availability, combined with the ease of exploitation (network vector, low attack complexity, no privileges required, but user interaction is needed). The vulnerability is classified under CWE-79, which corresponds to improper neutralization of input during web page generation. Although no known exploits are currently reported in the wild, the public disclosure and high severity score indicate a significant risk to Jenkins users relying on this plugin. The vulnerability affects Jenkins instances that integrate with the Health Advisor plugin and communicate with the Health Advisor server, making it a concern for organizations using Jenkins for their software development pipelines.

For European organizations, this vulnerability poses a substantial risk to the security and integrity of their CI/CD pipelines. Jenkins is widely adopted across Europe in both private and public sectors for automating software builds, testing, and deployment. Exploitation of this XSS vulnerability could lead to unauthorized access to sensitive build configurations, leakage of credentials or tokens used in automation, and potential insertion of malicious code into software artifacts. This could result in compromised software supply chains, data breaches, and disruption of development workflows. Given the critical role of Jenkins in software delivery, an attacker leveraging this vulnerability could impact the confidentiality, integrity, and availability of software development processes, potentially affecting compliance with European data protection regulations such as GDPR. Furthermore, organizations in regulated industries like finance, healthcare, and critical infrastructure could face heightened risks due to the potential for operational disruption and reputational damage.

To mitigate this vulnerability, European organizations should immediately update the Jenkins Health Advisor by CloudBees Plugin to a version that addresses this XSS flaw once available. Until a patch is released, organizations should consider disabling the plugin or restricting access to the Jenkins instances hosting the plugin to trusted users only. Implementing strict Content Security Policy (CSP) headers on Jenkins web interfaces can help reduce the impact of XSS attacks by limiting the execution of unauthorized scripts. Additionally, network-level controls should be applied to restrict communication between Jenkins and the Health Advisor server to trusted endpoints. Regular security audits and monitoring of Jenkins logs for unusual activity related to plugin responses can aid in early detection of exploitation attempts. Organizations should also educate Jenkins administrators and developers about the risks of XSS and enforce the principle of least privilege for Jenkins user accounts to minimize potential damage from compromised sessions.