{"cve":"CVE-2025-46570","nvd":{"published":"2025-05-29T17:15:21.327","modified":"2026-06-17T09:26:38.523","status":"Analyzed","description":"vLLM is an inference and serving engine for large language models (LLMs). Prior to version 0.9.0, when a new prompt is processed, if the PageAttention mechanism finds a matching prefix chunk, the prefill process speeds up, which is reflected in the TTFT (Time to First Token). These timing differences caused by matching chunks are significant enough to be recognized and exploited. This issue has been patched in version 0.9.0.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:N/A:N","score":2.6},"cwes":["CWE-203","CWE-208"],"references":["https://github.com/vllm-project/vllm/commit/77073c77bc2006eb80ea6d5128f076f5e6c6f54f","https://github.com/vllm-project/vllm/pull/17045","https://github.com/vllm-project/vllm/security/advisories/GHSA-4qjh-9fv9-r85r"],"products":["vllm:vllm"],"source":"nvd","synced_at":"2026-10-19T22:01:57.636215869+00:00"},"epss":{"cve":"CVE-2025-46570","score":0.0043,"percentile":0.37256,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-4qjh-9fv9-r85r","url":"https://osv.dev/vulnerability/GHSA-4qjh-9fv9-r85r","summary":"Potential Timing Side-Channel Vulnerability in vLLM’s Chunk-Based Prefix Caching","modified":"2026-08-07T08:12:07.737844771Z","packages":[{"ecosystem":"PyPI","name":"vllm","purl":"pkg:pypi/vllm","ranges":["<0.9.0"],"fixed":["0.9.0"]}]},{"id":"PYSEC-2025-53","url":"https://osv.dev/vulnerability/PYSEC-2025-53","summary":"","modified":"2025-06-26T21:44:36.898654Z","packages":[{"ecosystem":"PyPI","name":"vllm","purl":"pkg:pypi/vllm","ranges":["<0.9.0"],"fixed":["0.9.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}