CVE-2025-59425 HIGH

CVE-2025-59425: vLLM vulnerable to timing attack at bearer auth

Vendor Vllm-Project
Product vllm
Weakness CWE-385
Published October 7, 2025
Last update October 7, 2025

CVSS base score

7.5/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality High
Integrity None

CVSS vector

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

What the vulnerability does

01Description

vLLM is an inference and serving engine for large language models (LLMs). Before version 0.11.0rc2, the API key support in vLLM performs validation using a method that was vulnerable to a timing attack. API key validation uses a string comparison that takes longer the more characters the provided API key gets correct. Data analysis across many attempts could allow an attacker to determine when it finds the next correct character in the key sequence. Deployments relying on vLLM's built-in API key validation are vulnerable to authentication bypass using this technique. Version 0.11.0rc2 fixes the issue.

Key dates

02Disclosure timeline

October 7, 2025 CVE published
October 7, 2025 Record updated