ComfyUI v0.23.0 contains an unsafe deserialization vulnerability in the LoadTrainingDataset node that allows unauthenticated remote attackers to execute arbitrary Python code by uploading a crafted pickle file and triggering its deserialization. Attackers can upload a malicious shard_*.pkl file via the unauthenticated POST /upload/image endpoint and then queue a workflow graph via POST /prompt referencing the uploaded file, causing torch.load to deserialize the attacker-controlled pickle payload using __reduce__ and execute arbitrary commands as the ComfyUI process user.