CVE-2026-73558 MEDIUM

CVE-2026-73558: vLLM: Cross-User Data Leak Vulnerability

Vendor Vllm-Project
Product vllm
Weakness CWE-190
Published August 13, 2026
Last update August 13, 2026

CVSS base score

5.3/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction Required
Confidentiality High
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N

What the vulnerability does

01Description

vLLM is an inference and serving engine for large language models. Prior to 0.27.0, an integer overflow in blockIdx.x * 2 * d in activation_kernels.cu can cause act_and_mul_kernel to consume another batched user's input, allowing a request processed in the same inference batch to receive a partial or complete copy of another user's inference result. This issue is fixed in version 0.27.0.

Key dates

02Disclosure timeline

August 13, 2026 CVE published
August 13, 2026 Record updated