Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
The "JsonErrorReportValve" in Apache Tomcat versions 8.5.83, 9.0.40 through 9.0.68, and 10.0.0-M10 through 10.1.1 did 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.
CWE-74 - Injection
Listed as the number one web application security risk on the 'OWASP Top Ten', injection attacks are widespread and dangerous, especially in legacy applications. Injection attacks are a class of vulnerabilities in which an attacker injects untrusted data into a web application that gets processed by an interpreter, altering the program's execution. This can result in data loss/theft, loss of data integrity, denial of service, and even compromising the entire system.