The imgaug library version 0.4.0 and earlier contains an insecure deserialization vulnerability in the BackgroundAugmenter class within the multicore.py module. This vulnerability arises because the class uses Python's pickle module to deserialize data from a multiprocessing queue without validation. An attacker able to influence the queue's data can supply a malicious pickle payload that executes arbitrary code in the worker process context. This can lead to remote or local code execution depending on how the library is deployed.