CVE-2024-8939: vLLM Denial of Service via the best_of parameter
A vulnerability was found in the ilab model serve component, where improper handling of the bestof parameter in the vllm JSON web API can lead to a Denial of Service (DoS). The API used for LLM-based sentence or chat completion accepts a bestof parameter to return the best completion from several options.
Published Sep 17, 2024
Affected packages
vllm
- Ecosystem
- PyPI
- Affected
- <= 0.5.0.post1
- Fixed in
- No patched version yet
- Check
pip show vllm
Advisory details
From the GitHub Advisory Database (CC BY 4.0).
A vulnerability was found in the ilab model serve component, where improper handling of the best_of parameter in the vllm JSON web API can lead to a Denial of Service (DoS). The API used for LLM-based sentence or chat completion accepts a best_of parameter to return the best completion from several options. When this parameter is set to a large value, the API does not handle timeouts or resource exhaustion properly, allowing an attacker to cause a DoS by consuming excessive system resources. This leads to the API becoming unresponsive, preventing legitimate users from accessing the service.
References
How this page is made: the data panel comes from the GitHub Advisory Database, CISA’s KEV catalog, the NVD and FIRST EPSS, and updates twice a day. No analysis has been written for this entry yet. Methodology
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