Dromara lamp-cloud Message Template GroovyClassLoader.parseClass special elements used in a template engine

A vulnerability has been found in Dromara lamp-cloud up to 5.6.2. Impacted is the function GroovyClassLoader.parseClass of the component Message Template Handler. Such manipulation of the argument DefMsgTemplate.content leads to improper neutralization of special elements used in a template engine. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.