{"id":"CVE-2026-73559","title":"vLLM is an inference and serving engine for large language models","summary":"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…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-400"],"vendor":"vllm","product":"vllm","affected":["vllm >= 0.19.0, < 0.26.0"],"patched":["vllm 0.26.0"],"published":"2026-08-13","updated":"2026-09-09","sourceUpdated":"2026-09-09T20:58:37.713","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-73559","references":[{"url":"https://github.com/vllm-project/vllm/commit/675f4295cdfe0d870471c2b51bfeca3a68a9569e","label":"security-advisories@github.com"},{"url":"https://github.com/vllm-project/vllm/pull/47845","label":"security-advisories@github.com"},{"url":"https://github.com/vllm-project/vllm/releases/tag/v0.26.0","label":"security-advisories@github.com"},{"url":"https://github.com/vllm-project/vllm/security/advisories/GHSA-87x5-vmc3-756j","label":"security-advisories@github.com"},{"url":"https://github.com/vllm-project/vllm/security/advisories/GHSA-87x5-vmc3-756j","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-73559"},{"url":"https://github.com/advisories/GHSA-87x5-vmc3-756j"},{"url":"https://github.com/vllm-project/vllm"}],"tags":["nvd","ghsa","pip","osv"],"epss":0.00472,"epssPercentile":0.39978,"aliases":["GHSA-87x5-vmc3-756j","PYSEC-2026-3704"],"ecosystem":"pip","ingestedAt":"2026-08-13T19:05:04.705Z","slug":"CVE-2026-73559","body":"## Overview\n\nvLLM 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-73559)\n\nAffected packages:\n\n- `vllm >= 0.19.0, < 0.26.0`\n\nPatched in:\n\n- `vllm 0.26.0`\n\nSource: https://github.com/advisories/GHSA-87x5-vmc3-756j","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}