vLLM before 0.29.0 validates allowed_token_ids against tokenizer length instead of model output logits width in SamplingParams._validate_allowed_token_ids(). Attackers can supply token IDs above the output vocabulary that pass validation, causing LogitBiasState to corrupt GPU logits state and allow concurrent requests to sample tokens outside their allowlists.
History

Wed, 23 Sep 2026 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-787
References
Metrics threat_severity

None

threat_severity

Moderate


Mon, 21 Sep 2026 19:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

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


Fri, 18 Sep 2026 21:30:00 +0000

Type Values Removed Values Added
Description vLLM before 0.29.0 validates allowed_token_ids against tokenizer length instead of model output logits width in SamplingParams._validate_allowed_token_ids(). Attackers can supply token IDs above the output vocabulary that pass validation, causing LogitBiasState to corrupt GPU logits state and allow concurrent requests to sample tokens outside their allowlists.
Title vLLM before 0.29.0 Cross-Request Logits Corruption via allowed_token_ids
First Time appeared Vllm
Vllm vllm
Weaknesses CWE-129
CPEs cpe:2.3:a:vllm:vllm:*:*:*:*:*:*:*:*
Vendors & Products Vllm
Vllm vllm
References
Metrics cvssV3_1

{'score': 3.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N'}

cvssV4_0

{'score': 6.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published: 2026-09-18T19:06:06.001Z

Updated: 2026-09-24T14:23:15.056Z

Reserved: 2026-09-18T18:16:47.489Z

Link: CVE-2026-93840

cve-icon Vulnrichment

Updated: 2026-09-21T18:29:57.171Z

cve-icon NVD

Status : Analyzed

Published: 2026-09-18T20:17:34.200

Modified: 2026-09-28T18:36:00.710

Link: CVE-2026-93840

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-09-18T19:06:06Z

Links: CVE-2026-93840 - Bugzilla