Deserialization of Untrusted Data
GoCD is a continuous delivery server. GoCD helps you automate and streamline the build-test-release cycle for continuous delivery of your product. GoCD versions prior to 21.1.0 are vulnerable to remote code execution on the server from a malicious or compromised agent. The Spring RemoteInvocation endpoint exposed agent communication and allowed deserialization of arbitrary java objects, as well as subsequent remote code execution. Exploitation requires agent-level authentication, thus an attacker would need to either compromise an existing agent, its network communication or register a new agent to practically exploit this vulnerability. This issue is fixed in GoCD version 21.1.0. There are currently no known workarounds.
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.