{"id":"CVE-2026-44223","summary":"vLLM: extract_hidden_states speculative decoding crashes server on any request with penalty parameters","details":"vLLM is an inference and serving engine for large language models (LLMs). From 0.18.0 to before 0.20.0, the extract_hidden_states speculative decoding proposer in vLLM returns a tensor with an incorrect shape after the first decode step, causing a RuntimeError that crashes the EngineCore process. The crash is triggered when any request in the batch uses sampling penalty parameters (repetition_penalty, frequency_penalty, or presence_penalty). A single request with a penalty parameter (e.g., \"repetition_penalty\": 1.1) is sufficient to crash the server. This vulnerability is fixed in 0.20.0.","aliases":["GHSA-83vm-p52w-f9pw","PYSEC-2026-145"],"modified":"2026-07-08T08:02:15.809494620Z","published":"2026-05-12T19:58:40.862Z","database_specific":{"cwe_ids":["CWE-131","CWE-704"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44223.json","cna_assigner":"GitHub_M"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44223.json"},{"type":"ADVISORY","url":"https://github.com/vllm-project/vllm/security/advisories/GHSA-83vm-p52w-f9pw"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-44223"},{"type":"FIX","url":"https://github.com/vllm-project/vllm/pull/38610"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/vllm-project/vllm","events":[{"introduced":"bcf2be96120005e9aea171927f85055a6a5c0cf6"},{"fixed":"88d34c6409e9fb3c7b8ca0c04756f061d2099eb1"}],"database_specific":{"cpe":"cpe:2.3:a:vllm:vllm:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0.18.0"},{"fixed":"0.20.0"}],"source":["AFFECTED_FIELD","CPE_RANGE"]}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-44223.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}