Vulnerability in Vllm

CVE-2025-48943

vLLM is an inference and serving engine for large language models (LLMs). Version 0.8.0 up to but excluding 0.9.0 have a Denial of Service (ReDoS) that causes the vLLM server to crash if an invalid regex was provided while using structured output. This vulnerability is similar to GHSA-6qc9-v4r8-22xg/CVE-2025-48942, but for regex instead of a JSON schema. Version 0.9.0 fixes the issue.

EPSS: 0.004 (32.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-48943?
CVE-2025-48943 is a medium-severity vulnerability in Vllm, classified under CWE-248. CVSS score: 6.5/10. Published 2025-05-30.
How severe is CVE-2025-48943?
Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2025-48943 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.