CVE-2026-56340: vLLM multimodal embeddings processing missing sparse tensor validation

Summary

vLLM versions 0.10.2 up to but not including 0.13.0 lack sparse tensor validation in multimodal embeddings processing. Because PyTorch disables sparse tensor invariant checks by default, crafted embedding requests with malformed (negative or out-of-bounds) tensor indices can crash the server or exhaust resources when the prompt-embeds feature is enabled. The source also notes potential out-of-bounds write (write-what-where) memory corruption. This continues CVE-2025-62164, whose earlier fix only disabled the feature by default.

Mitigation

The source does not state a fix yet. Check the original advisory for updates.

Affected packages in the Exposure Registry

Matched by package name and ecosystem. Each entry shows whether the package delegates to a language model and how many tracked packages depend on it.

• vllmPyPILLM dependency since 2023-08-25 · 15 tracked dependents

Topics

• Inference infrastructure

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