CVE-2025-48942: vLLM server crash via invalid json_schema in /v1/completions Guided Param

Summary

CVE-2025-48942 affects vLLM, an inference and serving engine for large language models, in versions 0.8.0 up to but excluding 0.9.0. Sending an invalid json_schema as a Guided Param to the /v1/completions API crashes the vllm server. It is similar to GHSA-9hcf-v7m4-6m2j/CVE-2025-48943, but applies to regex instead of a JSON schema.

Mitigation

Version 0.9.0 fixes the issue.

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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