Deserialization of Untrusted Data
When an application with unsupported Codehaus versions of Groovy through 1.7.0 through 2.4.3, Apache Groovy through 2.4.7 on classpath uses standard Java serialization mechanisms, e.g. to communicate between servers or to store local data, it was possible for an attacker to bake a special serialized object that will execute code directly when deserialized. All applications which rely on serialization and do not isolate the code which deserializes objects were subject to this vulnerability.
CWE-502 - Deserialization of Untrusted Data
Deserialization of untrusted data vulnerabilities enable an attacker to replace or manipulate a serialized object, replacing it with malicious data. When the object is deserialized at the victim's end the malicious data is able to compromise the victim’s system. The exploit can be devastating, its impact may range from privilege escalation, broken access control, or denial of service attacks to allowing unauthorized access to the application's internal code and logic which can compromise the entire system.