IBM Db2 for Linux, UNIX and Windows (includes Db2 Connect Server) 11.5.0 - 11.5.9 and 12.1.0 - 12.1.3 could allow an authenticated user to cause a denial of service using a specially crafted SQL statement including XML that performs uncontrolled recursion.
The product does not properly control the amount of recursion that takes place, consuming excessive resources, such as allocated memory or the program stack.