PYSEC-2026-3998

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Import Source
https://github.com/pypa/advisory-database/blob/main/vulns/vllm/PYSEC-2026-3998.yaml
JSON Data
https://api.osv.dev/v1/vulns/PYSEC-2026-3998
Aliases
Published
2026-09-18T20:17:34Z
Modified
2026-09-29T09:00:03Z
Severity
  • 5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N CVSS Calculator
Summary
[none]
Details

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.

References

Affected packages

PyPI / vllm

Package

Name
vllm
View open source insights on deps.dev
Purl
pkg:pypi/vllm

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
0.29.0

Affected versions

0.*
0.0.1
0.1.0
0.1.1
0.1.2
0.1.3
0.1.4
0.1.5
0.1.6
0.1.7
0.2.0
0.2.1
0.2.1.post1
0.2.2
0.2.3
0.2.4
0.2.5
0.2.6
0.2.7
0.3.0
0.3.1
0.3.2
0.3.3
0.4.0
0.4.0.post1
0.4.1
0.4.2
0.4.3
0.5.0
0.5.0.post1
0.5.1
0.5.2
0.5.3
0.5.3.post1
0.5.4
0.5.5
0.6.0
0.6.1
0.6.1.post1
0.6.1.post2
0.6.2
0.6.3
0.6.3.post1
0.6.4
0.6.4.post1
0.6.5
0.6.6
0.6.6.post1
0.7.0
0.7.1
0.7.2
0.7.3
0.8.0
0.8.1
0.8.2
0.8.3
0.8.4
0.8.5
0.8.5.post1
0.9.0
0.9.0.1
0.9.1
0.9.2
0.10.0
0.10.1
0.10.1.1
0.10.2
0.11.0
0.11.1
0.11.2
0.12.0
0.13.0
0.14.0
0.14.1
0.15.0
0.15.1
0.16.0
0.17.0
0.17.1
0.18.0
0.18.1
0.19.0
0.19.1
0.20.0
0.20.1
0.20.2
0.21.0
0.22.0
0.22.1
0.23.0
0.24.0
0.25.0
0.25.1
0.26.0
0.27.0
0.27.1
0.28.0

Database specific

source 
"https://github.com/pypa/advisory-database/blob/main/vulns/vllm/PYSEC-2026-3998.yaml"