The Jenkins 2.73.1 and earlier, 2.83 and earlier default form control for passwords and other secrets, <f:password/>, supports form validation (e.g. for API keys). The form validation AJAX requests were sent via GET, which could result in secrets being logged to a HTTP access log in non-default configurations of Jenkins, and made available to users with access to these log files. Form validation for <f:password/> is now always sent via POST, which is typically not logged.