CVE-2026-34755 MEDIUM

CVE-2026-34755: vLLM Affected by Denial of Service via Unbounded Frame Count in video/jpeg Base64 Processing

Vendor Vllm-Project
Product vllm
Weakness CWE-770 · Uncontrolled resource consumption
Published April 6, 2026
Last update June 30, 2026

CVSS base score

6.5/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality None
Integrity None

CVSS vector

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

What the vulnerability does

01Description

vLLM is an inference and serving engine for large language models (LLMs). From 0.7.0 to before 0.19.0, the VideoMediaIO.load_base64() method at vllm/multimodal/media/video.py splits video/jpeg data URLs by comma to extract individual JPEG frames, but does not enforce a frame count limit. The num_frames parameter (default: 32), which is enforced by the load_bytes() code path, is completely bypassed in the video/jpeg base64 path. An attacker can send a single API request containing thousands of comma-separated base64-encoded JPEG frames, causing the server to decode all frames into memory and crash with OOM. This vulnerability is fixed in 0.19.0.

Key dates

02Disclosure timeline

April 6, 2026 CVE published
June 30, 2026 Record updated