CVE-2022-45397 is a critical vulnerability affecting the Jenkins OSF Builder Suite :: XML Linter Plugin version 1.0.2 and earlier. The vulnerability arises because the XML parser used by the plugin is not properly configured to prevent XML External Entity (XXE) attacks. XXE is a type of attack against an application that parses XML input, where an attacker can exploit the XML parser's ability to process external entities. This can lead to disclosure of confidential data, server-side request forgery (SSRF), denial of service (DoS), and potentially remote code execution depending on the environment. The vulnerability is classified under CWE-611 (Improper Restriction of XML External Entity Reference). The CVSS v3.1 score is 9.8 (critical), reflecting the high impact on confidentiality, integrity, and availability, with no privileges or user interaction required and network attack vector. Jenkins is a widely used open-source automation server for continuous integration and continuous delivery (CI/CD), and plugins like the OSF Builder Suite :: XML Linter are commonly used to validate XML files in build pipelines. Exploiting this vulnerability could allow attackers to read sensitive files on the Jenkins server, perform SSRF attacks to internal systems, or cause service disruption, severely impacting the CI/CD infrastructure.

For European organizations, this vulnerability poses a significant risk due to the widespread adoption of Jenkins in software development and DevOps environments. Compromise of Jenkins servers can lead to exposure of sensitive source code, credentials, and internal network information, which can cascade into broader organizational breaches. The ability to execute SSRF or DoS attacks can disrupt critical software delivery pipelines, affecting business continuity. Given the critical nature of the vulnerability and the fact that it requires no authentication or user interaction, attackers can remotely exploit vulnerable Jenkins instances exposed to the internet or accessible within corporate networks. This threat is particularly concerning for sectors with high reliance on automated software deployment such as finance, telecommunications, manufacturing, and government agencies across Europe. The lack of known exploits in the wild currently does not diminish the urgency, as the vulnerability is straightforward to exploit and could be weaponized rapidly.

European organizations should immediately audit their Jenkins environments to identify installations of the OSF Builder Suite :: XML Linter Plugin version 1.0.2 or earlier. Since no patch links are currently provided, organizations should consider the following mitigations: 1) Disable or remove the vulnerable XML Linter Plugin until a patched version is available. 2) Restrict network access to Jenkins servers, ensuring they are not exposed to the public internet and are protected by firewalls and VPNs. 3) Implement strict input validation and sanitization for XML inputs processed by Jenkins plugins. 4) Monitor Jenkins logs for unusual XML parsing errors or unexpected external entity requests. 5) Employ runtime application self-protection (RASP) or web application firewalls (WAF) that can detect and block XXE attack patterns. 6) Stay updated with Jenkins security advisories to apply patches promptly once released. 7) Conduct security awareness training for DevOps teams on secure plugin usage and configuration. These steps will reduce the attack surface and mitigate exploitation risks until an official patch is available.