GitHub Advisoryadvisory · PyPI
GHSA-7h4p-rffg-7823 vLLM: temperature=NaN and temperature=Infinity bypass validation and propagate to GPU kernels
MEDIUM
Official page ↗
- Aliases
- CVE-2026-54235
- Ecosystem
- PyPI
- Packages
- vllm
- Severity
- Moderate
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
- Weaknesses
- CWE-1287
- Reviewed
- 2026-06-17
Affected packages
• PyPI vllm: >= 0.8.5, < 0.24.0 → fixed in 0.24.0
Description
Summary
All temperature validation gates use comparison operators (``), which silently evaluate to `False` for `NaN` and for positive `Infinity` in Python's IEEE 754 float semantics. Both values pass every guard and propagate to GPU sampling kernels, where they produce undefined behavior or CUDA errors that can crash the inference worker. Note: `-Infinity` is correctly caught.
Root Cause
`sampling_params.py:384`:
```python
if 0 < self.temperature < _MAX_TEMP: # NaN → False; +Inf → False
```
`sampling_params.py:462`:
```python
if self.temperature < 0.0: # NaN → False; +Inf → False
raise VLLMValidationError(...)
```
No `math.isnan()` or `math.isinf()` check exists anywhere in `sampling_params.py`.
Python semantics (verified): `float('nan') < 0.0` → `False`, `float('inf') < 0.0` → `False`.
Impact
Crash of inference worker on GPU kernel execution with NaN/Inf softmax input, degrading service for all concurrent users.
Remediation
Add `math.isfinite(self.temperature)` check in `_verify_args()`. Reject non-finite float values with a 400 error.
Fix
A fix for this vulnerability was merged here: https://github.com/vllm-project/vllm/pull/45116
Related
Alias · CVE (1)
- CVE-2026-54235 vLLM is an inference and serving engine for large language models (LLMs). vulnerability
Weakness · CWE (1)
- CWE-1287 Improper Validation of Specified Type of Input weakness
References
- https://github.com/vllm-project/vllm/security/advisories/GHSA-7h4p-rffg-7823 web
- https://nvd.nist.gov/vuln/detail/CVE-2026-54235 advisory
- https://github.com/vllm-project/vllm/pull/45116 web
- https://github.com/vllm-project/vllm/commit/d598d239737cfa37bcfcb98886ec3f3557fc7198 web
- https://github.com/advisories/GHSA-7h4p-rffg-7823 advisory
- https://github.com/pypa/advisory-database/tree/main/vulns/vllm/PYSEC-2026-3405.yaml web
- https://github.com/vllm-project/vllm package
- https://pypi.org/project/vllm web