CVE-2026-56672

ComfyUI is a node-based diffusion model GUI, API, and backend. Prior to 0.28.0, GET /userdata/{file} served user-controlled HTML and SVG files with extension-derived content types, allowing stored cross-site scripting in the ComfyUI origin and access to browser-stored API tokens, settings, workflows, and authenticated-equivalent API calls. The handler used web.FileResponse(path), so an uploaded .html/.svg was served as text/html/image/svg+xml. POST /userdata stores arbitrary request bodies (confined to the user's userdata directory). When a victim navigated to the file URL, the embedded script executed same-origin. The /view endpoint already forced dangerous MIME types to download; that protection had never been applied to /userdata. This issue is fixed in version 0.28.0.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/Comfy-Org/ComfyUI/commit/96e0e3585b41e1417442eaa14ec57f7b4ffcb5e0
https://github.com/Comfy-Org/ComfyUI/releases/tag/v0.28.0
https://github.com/Comfy-Org/ComfyUI/security/advisories/GHSA-53g8-45wq-pcv8

Configurations

No configuration.

History

31 Jul 2026, 06:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-31 06:16

Updated : 2026-07-31 11:17

NVD link : CVE-2026-56672

Mitre link : CVE-2026-56672

CVE.ORG link : CVE-2026-56672

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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