CVE-2025-67639 is a CSRF vulnerability in Jenkins, a widely used automation server for continuous integration and continuous delivery. The vulnerability exists in Jenkins versions 2.540 and earlier, including LTS 2.528.2 and earlier, allowing attackers to craft malicious web requests that cause users to unknowingly log into the attacker’s account. This attack vector leverages the trust a user’s browser has in the Jenkins server, bypassing authentication controls by exploiting the lack of proper CSRF protections. When a user interacts with a malicious link or webpage, the attacker can hijack the session or force actions under the attacker’s identity, potentially leading to unauthorized access to build jobs, credentials, or pipeline configurations. Although no public exploits have been reported, the vulnerability’s presence in widely deployed Jenkins versions makes it a critical concern. The absence of a CVSS score indicates the need for manual severity assessment. The vulnerability affects the integrity of Jenkins environments and can lead to privilege escalation or unauthorized modifications. Jenkins is heavily used in European enterprises for software development and deployment, making this vulnerability a significant risk for operational security. The vulnerability requires user interaction but no authentication, increasing its attack surface. The lack of immediate patches necessitates proactive mitigation steps to reduce exposure.

For European organizations, this vulnerability threatens the integrity and trustworthiness of their CI/CD pipelines. Successful exploitation can allow attackers to perform unauthorized actions, such as modifying build configurations, injecting malicious code into software builds, or accessing sensitive credentials stored within Jenkins. This can lead to supply chain compromises, data breaches, and disruption of software delivery processes. Organizations in sectors with stringent compliance requirements, such as finance, healthcare, and critical infrastructure, face heightened risks due to potential regulatory violations and operational downtime. The vulnerability’s exploitation could also undermine the security of downstream systems that rely on Jenkins for automated deployments. Given Jenkins’ widespread adoption in Europe’s technology and industrial sectors, the impact could be broad and severe if not addressed promptly.

1. Monitor Jenkins security advisories closely and apply official patches immediately once released. 2. Enable Jenkins’ built-in CSRF protection features if not already active, ensuring that all requests include valid CSRF tokens. 3. Restrict access to Jenkins instances using network segmentation, VPNs, or IP whitelisting to limit exposure to trusted users only. 4. Educate users about the risks of clicking on suspicious links or visiting untrusted websites while logged into Jenkins. 5. Implement multi-factor authentication (MFA) to reduce the risk of session hijacking. 6. Regularly audit Jenkins user sessions and logs for unusual login patterns or unauthorized actions. 7. Consider deploying web application firewalls (WAFs) to detect and block CSRF attack attempts. 8. Use role-based access control (RBAC) to minimize privileges assigned to users and service accounts within Jenkins. 9. Isolate Jenkins environments from critical production systems to contain potential breaches. 10. Conduct penetration testing and vulnerability assessments focused on Jenkins to identify and remediate security gaps.