CVE-2026-34760Network attack vector

Audio-model decision manipulation via unweighted downmixing

Published Apr 2, 2026 · Updated Apr 2, 2026

Improper input validation in vLLM 0.5.5 and later, before 0.18.0, allows remote authenticated users to manipulate audio-model decisions. The Librosa to_mono path averages every channel with numpy.mean instead of applying speaker-aware downmix weights. Crafted multichannel audio can sound benign in ordinary playback while its LFE or later channels alter transcription, moderation, or voice-authentication results.

CVSS severity5.9
Medium
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in vLLM 0.5.5 and later, before 0.18.0, allows remote authenticated users to manipulate audio-model decisions. The Librosa to_mono path averages every channel with numpy.mean instead of applying speaker-aware downmix weights. Crafted multichannel audio can sound benign in ordinary playback while its LFE or later channels alter transcription, moderation, or voice-authentication results.

The record

CVE
CVE-2026-34760
Published
Apr 2, 2026
Updated
Apr 2, 2026
Vendor
vLLM Project
Product
vLLM
Classifications
CWE-20, T1027
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 2, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 2, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 0.5.5, < 0.18.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

vLLM Project · vLLMversion=>= 0.5.5, < 0.18.0

Published CVSS scores

5.9GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L
7.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1027Obfuscated Files or Information

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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