CVE-2026-56340

vLLM versions >= 0.10.2 and < 0.13.0 are missing sparse tensor validation in multimodal embeddings processing. Because PyTorch disables sparse tensor invariant checks by default, an attacker can submit crafted embedding requests with malformed (negative or out-of-bounds) tensor indices, when the prompt-embeds feature is enabled, to trigger crashes or resource exhaustion (denial of service), with potential for out-of-bounds/write-what-where memory corruption. This continues CVE-2025-62164, whose prior fix only disabled the feature by default rather than addressing the root cause.

Affected products

Pytorch, Vllm

Vllm

< 0.13.0

Fix

Available

CVSS 3.1

8.8 HIGH

EPSS

0.4% (28th percentile)

Weakness

CWE-787, CWE-20

NVD status

Modified

Published

2026-06-20

No exploit for CVE-2026-56340 has been indexed yet. Our index is built from live traffic and upstream syncs, so this page can only say what it knows — not that no exploit exists.