CVE-2025-48943: vLLM denial of service through invalid regex in structured output

Summary

CVE-2025-48943 affects vLLM, an inference and serving engine for large language models, in versions 0.8.0 up to but excluding 0.9.0. An invalid regex supplied while using structured output triggers a ReDoS that crashes the vLLM server, a denial of service. The flaw is similar to GHSA-6qc9-v4r8-22xg/CVE-2025-48942, but applies to regex rather than 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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