CVE-2025-48956: vLLM denial of service through oversized HTTP GET request header

Summary

CVE-2025-48956 affects vLLM, an inference and serving engine for large language models, from 0.1.0 to before 0.10.1.1. A single HTTP GET request with an extremely large header, sent to an HTTP endpoint, triggers a Denial of Service that exhausts server memory and can crash the server or make it unresponsive. No authentication is required, so any remote user can exploit it.

Mitigation

Fixed in 0.10.1.1.

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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