CVE-2026-28414

Gradio is an open-source Python package designed for quick prototyping. Prior to version 6.7, Gradio apps running on Window with Python 3.13+ are vulnerable to an absolute path traversal issue that enables unauthenticated attackers to read arbitrary files from the file system. Python 3.13+ changed the definition of `os.path.isabs` so that root-relative paths like `/windows/win.ini` on Windows are no longer considered absolute paths, resulting in a vulnerability in Gradio's logic for joining paths safely. This can be exploited by unauthenticated attackers to read arbitrary files from the Gradio server, even when Gradio is set up with authentication. Version 6.7 fixes the issue.

An adversary identifies a company's internal ML demo portal running Gradio on a Windows server (common in enterprise ML teams). Using a simple HTTP GET request with a crafted path like /file=/windows/win.ini or /file=/../../../users/mluser/.env, the attacker bypasses Gradio's path validation because Python 3.13's os.path.isabs no longer flags root-relative paths as absolute on Windows. The attacker systematically reads .env files (harvesting Hugging Face tokens, OpenAI API keys, AWS credentials), model configuration files, and proprietary fine-tuning datasets — all without any credentials. With harvested cloud credentials, the attacker pivots to S3 buckets containing full training datasets and model artifacts.