{"id":"CVE-2026-115911","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-115911","generatedAt":"2026-10-28T01:12:02.734Z","title":"From 0.19.0 until 0.32.0, authenticated callers can supply a request chat template when no server-side --chat-template is configured, or a malicious model repository can provide a template that is compiled and rendered by tokenizer.apply_chat_template()…","description":"vLLM is an inference and serving engine for large language models. From 0.19.0 until 0.32.0, authenticated callers can supply a request chat template when no server-side --chat-template is configured, or a malicious model repository can provide a template that is compiled and rendered by tokenizer.apply_chat_template() without a wall-clock timeout, output-size limit, or iteration bound. Rendering runs in a ThreadPoolExecutor with one worker by default, so a nonterminating render can block /v1/responses and other chat-template users after the request ends, while an output-expanding render can exhaust server memory. Harmony models are not affected because they do not use this Jinja path. This issue is fixed in version 0.32.0.","published":"2026-10-26T17:17:19.000Z","lastModified":"2026-10-26T18:34:17.000Z","status":"Awaiting Analysis","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":6.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-400","CWE-770","CWE-834"],"affected":[],"epss":null,"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and no EPSS score yet. Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-26T17:17:19.000Z","detail":{"score":"6.5","severity":"MEDIUM","publishedAt":"2026-10-26T17:17:18.753Z"},"summary":"New CVE, medium severity (CVSS 6.5)."}],"references":[{"url":"https://github.com/vllm-project/vllm/commit/cff08b461e086523cee8bba5bd3c66d302625134","source":"security-advisories@github.com"},{"url":"https://github.com/vllm-project/vllm/pull/50300","source":"security-advisories@github.com"},{"url":"https://github.com/vllm-project/vllm/releases/tag/v0.32.0","source":"security-advisories@github.com"},{"url":"https://github.com/vllm-project/vllm/security/advisories/GHSA-542m-9234-8gvf","source":"security-advisories@github.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-115911","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}