Improper Validation of Array Index Affecting vllm package, versions [0.22.0,0.24.0)


Severity

Recommended
0.0
high
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

Exploit Maturity
Proof of Concept
EPSS
0.33% (24th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-PYTHON-VLLM-20158366
  • published27 Sept 2026
  • disclosed26 Sept 2026
  • creditUnknown

Introduced: 26 Sep 2026

NewCVE-2026-100652  (opens in a new tab)
CWE-129  (opens in a new tab)

How to fix?

Upgrade vllm to version 0.24.0 or higher.

Overview

vllm is an A high-throughput and memory-efficient inference and serving engine for LLMs

Affected versions of this package are vulnerable to Improper Validation of Array Index via missing vocabulary-bound validation of stop_token_ids in the Rust HTTP and gRPC frontends. When a request is submitted with min_tokens greater than zero and a stop_token_ids entry outside the range [0, vocab_size), the out-of-vocabulary token ID is forwarded through EngineCoreSamplingParams.all_stop_token_ids into MinTokensLogitsProcessor, where it is used as a CUDA tensor index in logits.index_put_. This triggers a device-side assertion that leaves EngineCore in a fatal state requiring a full service restart. The Rust frontends already validate neighboring token-ID fields such as prompt, allowed_token_ids, and logit_bias against vocabulary bounds, but apply no equivalent check to stop_token_ids before lowering the request into engine-facing sampling state.

References

CVSS Base Scores

version 4.0
version 3.1