Deserialization of Untrusted Data
Versions of MCollective prior to 2.10.4 deserialized YAML from agents without calling safe_load, allowing the potential for arbitrary code execution on the server. The fix for this is to call YAML.safe_load on input. This has been tested in all Puppet-supplied MCollective plugins, but there is a chance that third-party plugins could rely on this insecure behavior.
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.