{"id":"CVE-2025-46560","summary":"vLLM phi4mm: Quadratic Time Complexity in Input Token Processing\u200b leads to denial of service","details":"vLLM is a high-throughput and memory-efficient inference and serving engine for LLMs. Versions starting from 0.8.0 and prior to 0.8.5 are affected by a critical performance vulnerability in the input preprocessing logic of the multimodal tokenizer. The code dynamically replaces placeholder tokens (e.g., \u003c|audio_|\u003e, \u003c|image_|\u003e) with repeated tokens based on precomputed lengths. Due to \u200b\u200binefficient list concatenation operations\u200b\u200b, the algorithm exhibits \u200b\u200bquadratic time complexity (O(n²))\u200b\u200b, allowing malicious actors to trigger resource exhaustion via specially crafted inputs. This issue has been patched in version 0.8.5.","aliases":["GHSA-vc6m-hm49-g9qg","PYSEC-2026-2022"],"modified":"2026-08-12T03:51:21.633287605Z","published":"2025-04-30T00:24:53.750Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-1333"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/46xxx/CVE-2025-46560.json"},"references":[{"type":"WEB","url":"https://github.com/vllm-project/vllm/blob/8cac35ba435906fb7eb07e44fe1a8c26e8744f4e/vllm/model_executor/models/phi4mm.py#L1182-L1197"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/46xxx/CVE-2025-46560.json"},{"type":"ADVISORY","url":"https://github.com/vllm-project/vllm/security/advisories/GHSA-vc6m-hm49-g9qg"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-46560"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/vllm-project/vllm","events":[{"introduced":"966f933ee1cd7c9a41db60de5c7ff98657005251"},{"fixed":"ba41cc90e8ef7f236347b2f1599eec2cbb9e1f0d"}],"database_specific":{"cpe":"cpe:2.3:a:vllm:vllm:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0.8.0"},{"fixed":"0.8.5"}],"source":["AFFECTED_FIELD","CPE_RANGE"]}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-46560.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}