The vulnerability (CVE-2019-10400) stems from the groovy-sandbox library (version ≤1.22) used by the Jenkins Script Security Plugin. The plugin itself did not contain specific vulnerable functions in its codebase; instead, the issue arose from insufficient sandboxing logic in the dependency. The commit shows the plugin upgraded to groovy-sandbox 1.23 and added tests to block unsafe expressions (e.g., subexpressions in increment/decrement operations). The actual vulnerability resided in the library's handling of method/property names and subexpressions, not in the plugin's own functions. Thus, no plugin-specific functions are identified with high confidence.