vLLM is an inference and serving engine for large language models (LLMs). From version 0.5.5 to before version 0.18.0, Librosa defaults to using numpy.mean for mono downmixing (to_mono), while the international standard ITU-R BS.775-4 specifies a weighted downmixing algorithm. This discrepancy results in inconsistency between audio heard by humans (e.g., through headphones/regular speakers) and audio processed by AI models (Which infra via Librosa, such as vllm, transformer). This issue has been patched in version 0.18.0.
History

Tue, 07 Apr 2026 00:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-358
References
Metrics threat_severity

None

threat_severity

Moderate


Fri, 03 Apr 2026 15:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 03 Apr 2026 10:15:00 +0000

Type Values Removed Values Added
First Time appeared Vllm-project
Vllm-project vllm
Vendors & Products Vllm-project
Vllm-project vllm

Thu, 02 Apr 2026 20:30:00 +0000

Type Values Removed Values Added
Description vLLM is an inference and serving engine for large language models (LLMs). From version 0.5.5 to before version 0.18.0, Librosa defaults to using numpy.mean for mono downmixing (to_mono), while the international standard ITU-R BS.775-4 specifies a weighted downmixing algorithm. This discrepancy results in inconsistency between audio heard by humans (e.g., through headphones/regular speakers) and audio processed by AI models (Which infra via Librosa, such as vllm, transformer). This issue has been patched in version 0.18.0.
Title vLLM: Downmix Implementation Differences as Attack Vectors Against Audio AI Models
Weaknesses CWE-20
References
Metrics cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-04-02T18:59:49.638Z

Updated: 2026-04-03T14:42:34.842Z

Reserved: 2026-03-30T19:17:10.225Z

Link: CVE-2026-34760

cve-icon Vulnrichment

Updated: 2026-04-03T14:42:31.132Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-04-02T20:16:25.437

Modified: 2026-04-03T16:10:23.730

Link: CVE-2026-34760

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-04-02T18:59:49Z

Links: CVE-2026-34760 - Bugzilla