Denial of Service in vLLM from vLLM project

CVE-2026-56340

What is CVE-2026-56340?

The identified vulnerability in vLLM involves inadequate validation for sparse tensors within the processing of multimodal embeddings. Specifically, versions from 0.10.2 to below 0.13.0 lack essential checks against malformed tensor indices, which can be exploited by malicious actors. When using the prompt-embeds feature, an attacker may submit specially crafted embedding requests containing negative or out-of-bound indices, leading to system crashes or resource exhaustion. This issue is an extension of a prior vulnerability that only disabled the affected feature by default without resolving the underlying problem.

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