The vulnerability stems from missing permission checks in HTTP endpoints handling credential operations. Jenkins plugin patterns indicate credential-related endpoints typically use doFill[...]Items for dropdown population and doCheck[...] for validation. The security advisory specifically calls out credential ID enumeration via unprotected endpoints, which would map to these methods. While exact code isn't available, Jenkins' convention for form validation methods and the advisory's technical details support this mapping. Confidence is medium due to reliance on plugin conventions rather than direct patch inspection.