CVE-2026-73559vLLM: Completion prompt lists fan out into unbounded engine requests
Updated under an hour ago ()
Does this affect you?
It affects vllm-project vllm and 1 other product. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
vLLM is an inference and serving engine for large language models. From 0.19.0 until 0.26.0, the /v1/completions CompletionRequest.prompt field in vllm/entrypoints/openai/completion/protocol.py accepts an unbounded list[str] or list[list[int]], prompt_to_seq() in vllm/renderers/inputs/preprocess.py and OnlineRenderer.preprocess_completion() in vllm/renderers/online_renderer.py expand every element, and vllm/entrypoints/openai/completion/serving.py creates one engine generator and response slot per prompt, allowing an authenticated API client to exhaust CPU, memory, async scheduling capacity, engine request slots, and response buffering with one request. This issue is fixed in version 0.26.0.
- CVSS
- 6.5 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Weakness (CWE)
- CWE-400
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- GitHub_M
- NVD analysis
- Analyzed
- Record last updated
- Aug 14, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
vllm-project vllm vllm_project:vllm (from the name) | from 0.19.0, < 0.26.0 | CNA record |
vllm vllm vllm:vllm | from 0.19.0 before 0.26.0 | NVD |
References
- https://github.com/vllm-project/vllm/security/advisories/GHSA-87x5-vmc3-756jx-refsource-confirm, exploit, vendor-advisory
- https://github.com/vllm-project/vllm/pull/47845x-refsource-misc, issue-tracking, patch
- https://github.com/vllm-project/vllm/commit/675f4295cdfe0d870471c2b51bfeca3a68a9569ex-refsource-misc, patch
- https://github.com/vllm-project/vllm/releases/tag/v0.26.0x-refsource-misc, release-notes
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.