# CVE-2026-100654: vLLM before 0.29.0 Denial of Service via out-of-range stop_token_ids

> An authenticated user can cause a denial of service in vLLM by sending out-of-range stop token IDs, crashing the engine core.

- **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 26 Sep 2026
- **Updated:** 30 Sep 2026
- **Also known as:** GHSA-9fp6-6v59-w2jx, GHSA-v5gm-qgmv-gc6c, MINI-j85r-2c5h-4r98, MINI-r968-gvv5-7h4h, MINI-wq62-c945-3674

## What is CVE-2026-100654?

CVE-2026-100654 is a high-severity denial of service vulnerability in Vllm Vllm, published on 26 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official 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).

Weakness: CWE-129 (Improper Validation of Array Index)

## Which versions are affected by CVE-2026-100654?

It affects 1 product.


Products: Vllm Vllm.

## How do I fix CVE-2026-100654?

Upgrade to a fixed version.

## Is CVE-2026-100654 being exploited?

There is no known exploitation of CVE-2026-100654 in the wild and no public exploit code.

## Other vulnerabilities in Vllm Vllm

- [CVE-2025-32444](https://insights.sbomify.com/CVE-2025-32444/): vLLM Vulnerable to Remote Code Execution via Mooncake Integration (critical 10.0)
- [CVE-2026-22778](https://insights.sbomify.com/CVE-2026-22778/): vLLM leaks a heap address when PIL throws an error (critical 9.8)
- [CVE-2025-47277](https://insights.sbomify.com/CVE-2025-47277/): vLLM Allows Remote Code Execution via PyNcclPipe Communication Service (critical 9.8)
- [CVE-2024-11041](https://insights.sbomify.com/CVE-2024-11041/): Remote Code Execution in vllm-project/vllm (critical 9.8)
- [CVE-2026-48746](https://insights.sbomify.com/CVE-2026-48746/): vLLM: OpenAI auth bypass (critical 9.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-100654 and fix it if it is affected.

What it is: CVE-2026-100654 is a high-severity denial of service vulnerability in Vllm Vllm, published on 26 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-100654 in the wild and no public exploit code.

Affected product: Vllm Vllm. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-100654/ (Markdown: https://insights.sbomify.com/CVE-2026-100654/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-100654
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-100654
- OSV: https://osv.dev/vulnerability/CVE-2026-100654

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-100654/
Summaries are generated and may contain mistakes; the official description above is the record.