CVE-2024-23897 is a critical security vulnerability affecting Jenkins, a widely used open-source automation server for continuous integration and delivery. The flaw resides in the CLI command parser, which improperly handles arguments containing an '@' character followed by a file path. Instead of treating this as a literal argument, Jenkins replaces it with the contents of the referenced file on the controller's filesystem. This behavior is not disabled in Jenkins versions 2.441 and earlier, including LTS 2.426.2 and earlier, allowing unauthenticated attackers to exploit this feature remotely without any credentials or user interaction. By crafting CLI commands with specially formatted arguments, attackers can read arbitrary files, potentially exposing sensitive configuration files, credentials, private keys, or other critical data stored on the Jenkins controller. The vulnerability is classified under CWE-27 (Improper Handling of Special Elements in Input), and its CVSS 3.1 base score is 9.8, reflecting its criticality due to network attack vector, low attack complexity, no privileges required, no user interaction, and high impact on confidentiality, integrity, and availability. While no public exploits have been reported yet, the vulnerability's characteristics make it a prime target for attackers aiming to compromise CI/CD environments, steal secrets, or disrupt software delivery pipelines. The absence of patch links in the provided data suggests that mitigation or updates should be sought directly from Jenkins security advisories. Organizations relying on Jenkins should prioritize immediate risk assessment and remediation.

For European organizations, this vulnerability poses a severe risk to the confidentiality, integrity, and availability of their software development and deployment processes. Jenkins is extensively used across various industries in Europe, including finance, manufacturing, telecommunications, and government sectors, to automate build, test, and deployment workflows. Exploitation could lead to unauthorized disclosure of sensitive files such as credentials, private keys, and proprietary source code, enabling further attacks like lateral movement, privilege escalation, or supply chain compromise. The integrity of CI/CD pipelines could be undermined, resulting in the deployment of malicious or altered software. Availability impacts may arise if attackers disrupt Jenkins operations or cause denial of service. Given the critical role of Jenkins in modern DevOps environments, this vulnerability could have cascading effects on business continuity and regulatory compliance, especially under GDPR and other data protection frameworks. The lack of authentication requirement and ease of exploitation increase the likelihood of attacks, making it imperative for European entities to act swiftly.

1. Immediately upgrade Jenkins to the latest version where this vulnerability is patched; monitor official Jenkins security advisories for updates. 2. If patching is not immediately possible, disable the Jenkins CLI over remoting or restrict access to the CLI to trusted networks and users only. 3. Implement network-level controls such as firewall rules or VPNs to limit access to the Jenkins controller, especially blocking unauthenticated external access. 4. Audit Jenkins logs and configurations to detect any suspicious CLI usage or unauthorized file access attempts. 5. Rotate any credentials, keys, or secrets stored on the Jenkins controller that may have been exposed. 6. Employ runtime application self-protection (RASP) or endpoint detection and response (EDR) solutions to monitor for exploitation attempts. 7. Educate DevOps and security teams about this vulnerability and enforce the principle of least privilege for Jenkins users and agents. 8. Consider isolating Jenkins controllers in segmented network zones to minimize blast radius in case of compromise.