Hugging Face Transformers vulnerabilities

A vulnerability in Hugging Face Transformers (versions 4.49.0 through 5.8.1) allows remote Python files to be written to local disk without user consent when using GenerativePreTrainedModel.load_custom_generate(). The function fetches and caches a remote module file before performing the required trust_remote_code consent check, inverting the security model enforced by other code-loading paths. As a result, attacker-controlled Python code from custom_generate/generate.py is copied into the user's ~/.cache/huggingface/modules directory even if the user declines the trust prompt.

Hugging Face Transformers fails to validate shard filenames in checkpoint index files, allowing attackers to read arbitrary files outside the model directory. Malicious index files with parent-directory references or absolute paths can lead to file disclosure and filesystem reconnaissance.

Hugging Face Transformers up to version 5.8.0.dev0 has an arbitrary file write vulnerability via path traversal in save_pretrained(). Keys from chat_template are used as filenames without validation.