{"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","CWE-770"],"vendor":"vllm","product":"vllm","affected":["vllm >= 0.19.0, < 0.26.0"],"patched":["vllm 0.26.0"],"published":"2026-08-13","updated":"2026-09-28","sourceUpdated":"2026-09-28T18:41:23.210","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"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-73559.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-73559"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2515421"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-73559"},{"url":"https://access.redhat.com/errata/RHSA-2026:82415"},{"url":"https://access.redhat.com/errata/RHSA-2026:82368"},{"url":"https://access.redhat.com/errata/RHSA-2026:82061"},{"url":"https://access.redhat.com/errata/RHSA-2026:82059"},{"url":"https://access.redhat.com/errata/RHSA-2026:82371"}],"tags":["nvd","ghsa","pip","osv","csaf","vex","red-hat"],"aliases":["GHSA-87x5-vmc3-756j","PYSEC-2026-3704"],"ecosystem":"pip","ingestedAt":"2026-08-13T19:05:04.705Z","epss":0.00583,"epssPercentile":0.47671,"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## Affected\n\n- `vllm >= 0.19.0, < 0.26.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `vllm 0.26.0`\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\n\n## Vendor advisories\n\n- **RHSA-2026:82415** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82415)\n- **RHSA-2026:82368** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82368)\n- **RHSA-2026:82061** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82061)\n- **RHSA-2026:82059** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82059)\n- **RHSA-2026:82371** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82371)\n- **Red Hat VEX** · Moderate · affected: Red Hat OpenShift AI (RHOAI) · no fix planned: Red Hat OpenShift AI (RHOAI) · updated 2026-10-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-73559.json)","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}