CVE-2025-62426: vLLM denial of service via chat_template_kwargs in chat endpoints

Summary

CVE-2025-62426 affects vLLM, an inference and serving engine for large language models, from version 0.5.5 to before 0.11.1. The /v1/chat/completions and /tokenize endpoints use the chat_template_kwargs request parameter in code before validating it against the chat template. Crafted values of that parameter can block the API server for long periods, delaying all other requests.

Mitigation

This issue has been patched in version 0.11.1.

Affected packages in the Exposure Registry

Matched by package name and ecosystem. Each entry shows whether the package delegates to a language model and how many tracked packages depend on it.

• vllmPyPILLM dependency since 2023-08-25 · 15 tracked dependents

Topics

• Inference infrastructure

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