vLLM before 0.29.0 accepts user-controlled stop_token_ids on the OpenAI-compatible POST /v1/completions and POST /v1/chat/completions endpoints but validates only that the values are integers, not that each token id is within the model vocabulary/logits range. When min_tokens > 0, the stop token ids are used as logits indices to suppress stop tokens, so an out-of-range id reaches a CUDA indexing operation (index_put_) and triggers a device-side assertion. An authenticated API user can send a single malformed completion request that returns 500 Internal Server Error and puts EngineCore into a fatal state, causing subsequent requests to fail until the service is restarted (denial of service).
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References
History
Sat, 26 Sep 2026 13:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | vLLM before 0.29.0 accepts user-controlled stop_token_ids on the OpenAI-compatible POST /v1/completions and POST /v1/chat/completions endpoints but validates only that the values are integers, not that each token id is within the model vocabulary/logits range. When min_tokens > 0, the stop token ids are used as logits indices to suppress stop tokens, so an out-of-range id reaches a CUDA indexing operation (index_put_) and triggers a device-side assertion. An authenticated API user can send a single malformed completion request that returns 500 Internal Server Error and puts EngineCore into a fatal state, causing subsequent requests to fail until the service is restarted (denial of service). | |
| Title | vLLM before 0.29.0 Denial of Service via out-of-range stop_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
|
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Status: PUBLISHED
Assigner: VulnCheck
Published:
Updated: 2026-09-26T13:23:23.312Z
Reserved: 2026-09-26T02:33:07.899Z
Link: CVE-2026-100654
No data.
Status : Received
Published: 2026-09-26T14:16:48.100
Modified: 2026-09-26T14:16:48.100
Link: CVE-2026-100654
No data.
OpenCVE Enrichment
No data.
Weaknesses