CVE-2020-2111: 
Java vulnerability analysis and mitigation

CVE-2020-2111 is a stored cross-site scripting (XSS) vulnerability discovered in Jenkins Subversion Plugin versions 2.13.0 and earlier. The vulnerability was disclosed on February 12, 2020, affecting the Project Repository Base URL field form validation functionality. This security issue impacts Jenkins installations using the Subversion Plugin for source code management (Jenkins Advisory).

The vulnerability exists because the Subversion Plugin fails to properly escape error messages generated during the validation of the Project Repository Base URL field. The severity is rated as Medium according to the CVSS scoring system. The vulnerability was tracked as SECURITY-1725 internally by the Jenkins security team (Jenkins Advisory).

This stored XSS vulnerability can be exploited by users who have the ability to specify base URLs in the plugin configuration, particularly those with permissions to configure Multibranch Pipelines. When successfully exploited, it could allow attackers to execute malicious JavaScript code in the context of other users' browsers who view the affected Jenkins pages (Jenkins Advisory).

The vulnerability was fixed in Subversion Plugin version 2.13.1, which properly escapes the affected part of the error message. Users are advised to upgrade to this version or later to address the security issue. The fix ensures proper escaping of the error message content for the Project Repository Base URL field validation (Jenkins Advisory).