Description

vLLM is an inference and serving engine for large language models (LLMs). In versions 0.8.0 up to but excluding 0.9.0, hitting the /v1/completions API with a invalid json_schema as a Guided Param kills the vllm server. This vulnerability is similar GHSA-9hcf-v7m4-6m2j/CVE-2025-48943, but for regex instead of a JSON schema. Version 0.9.0 fixes the issue.

Classification

CVE ID: CVE-2025-48942

CVSS Base Severity: MEDIUM

CVSS Base Score: 6.5

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected Products

Vendor: vllm-project

Product: vllm

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.05% (probability of being exploited)

EPSS Percentile: 14.01% (scored less or equal to compared to others)

EPSS Date: 2025-06-18 (when was this score calculated)

References

https://nvd.nist.gov/vuln/detail/CVE-2025-48942
https://github.com/vllm-project/vllm/security/advisories/GHSA-6qc9-v4r8-22xg
https://github.com/vllm-project/vllm/issues/17248
https://github.com/vllm-project/vllm/pull/17623
https://github.com/vllm-project/vllm/commit/08bf7840780980c7568c573c70a6a8db94fd45ff

Timeline