Vulnerability in Vllm
CVE-2026-48746
vLLM is an inference and serving engine for large language models (LLMs). From 0.3.0 until 0.22.0, a vulnerability in ASGI web servers and starlette's trust on those web servers enables an authentication bypass of the OpenAI API AuthenticationMiddleware. It allows to use the API without providing the configured VLLM_API_KEY or --api-key. This vulnerability is fixed in 0.22.0.
Vulnerability class: HTTP Request Smuggling
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H.
EPSS exploit prediction
EPSS: 0.012 (65.7th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 66th percentile — 65.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.012 · newest: 0.012 · change: 0.000
Affected products
- Vllm
- Vllm-Project Vllm — versions >= 0.3.0, < 0.22.0
Weakness classification (CWE)
References
- github.com/vllm-project/vllm/security/advisories/GHSA-94f4-hr76-p5j6 (Third Party Advisory)
- github.com/vllm-project/vllm/pull/43426 (Issue Tracking)
- x41-dsec.de/lab/advisories/x41-2026-002-starlette (Third Party Advisory)
- 134c704f-9b21-4f2e-91b3-4a467353bcc0
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-48746?
- CVE-2026-48746 is a critical-severity vulnerability in Vllm, classified under Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling). CVSS score: 9.1/10. Published 2026-06-22.
- How severe is CVE-2026-48746?
- Critical severity. CVSS v3 base score is 9.1 out of 10.