The `JsonErrorReportValve` in Apache Tomcat 8.5.83, 9.0.40 to 9.0.68 and 10.1.0-M1 to 10.1.1 does not escape the `type`, `message` or `description` values. In some circumstances these are constructed from user provided data and it was therefore possible for users to supply values that invalidated or manipulated the JSON output.
Fix available through Seal Security. No upgrade required, protect your application instantly.
Fix without upgrading