A deserialization vulnerability exists in BentoMLs runner server in bentoml/bentoml versions <=1.3.4.post1. By setting specific parameters, an attacker can execute unauthorized arbitrary code on the server, causing severe harm. The vulnerability is triggered when the args-number parameter is greater than 1, leading to automatic deserialization and arbitrary code execution.
The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.