RCE in Vllm
CVE-2026-41523
vLLM is an inference and serving engine for large language models (LLMs). Prior to 0.22.0, an assert-based security check in vLLM's activation function loading allows any unauthenticated attacker to achieve arbitrary code execution on the server by publishing a malicious HuggingFace model, when vLLM runs in Python optimized mode (python -O or PYTHONOPTIMIZE=1). This vulnerability is fixed in 0.22.0.
Vulnerability class: RCE (Remote Code Execution)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.009 (58.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 59th percentile — 58.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000
Affected products
- Vllm
- Vllm-Project Vllm — versions < 0.22.0
Weakness classification (CWE)
References
- github.com/vllm-project/vllm/security/advisories/GHSA-q8gq-377p-jq3r (Exploit, Third Party Advisory)
- github.com/vllm-project/vllm/commit/b3c7ffcab82c2439726f8cb213800f6f38c023d3 (Patch)
- huntr.com/bounties/dcb05b04-e625-41e7-adbc-bbae0cc2d64c (Third Party Advisory)
- 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
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-41523?
- CVE-2026-41523 is a high-severity vulnerability in Vllm, classified under Code Injection. CVSS score: 7.5/10. Published 2026-06-22.
- How severe is CVE-2026-41523?
- High severity. CVSS v3 base score is 7.5 out of 10.