Summary
CVE-2026-56671 is an unauthenticated path traversal vulnerability in ComfyUI, the modular diffusion-model GUI, API, and backend from Comfy-Org. The flaw resides in the get_model_preview function and allows a remote attacker to read arbitrary image-decodable files and enumerate host paths without authentication. It affects all ComfyUI versions prior to 0.28.0 and is rated High (CVSS 7.5).
Technical details
- Root cause: The
get_model_previewfunction inapp/model_manager.pyjoins an unrestricted, route-captured filename to a base directory usingos.path.join(folder, filename)without a containment check (CWE-22, Improper Limitation of a Pathname to a Restricted Directory). - Trigger conditions: A request to the
/experiment/models/previewendpoint supplying a crafted filename. Bypass techniques include literal directory traversal sequences, percent-encoded equivalents, and absolute paths; thepath_indexparameter is used without bounds checking. - Attack vector: Network, no authentication and no user interaction required.
- Impact: Disclosure of confidentiality only — an attacker can read image-decodable files from arbitrary filesystem locations and enumerate host directory paths. No integrity or availability impact.
Affected software
- ComfyUI (Comfy-Org) — all versions prior to 0.28.0.
Severity
- CVSS v3.1 Base Score: 7.5 (High)
- Vector:
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Mitigation and recommended actions
- Immediate: Upgrade to ComfyUI 0.28.0 or later, which resolves the vulnerability.
- If no patch: Restrict network access to the ComfyUI instance — do not expose it directly to the internet; place it behind authentication, a reverse proxy, or a VPN, and block untrusted access to the
/experiment/models/previewendpoint.
How IONIX identifies potentially affected assets
IONIX matches the following signals against data already collected when it crawled the asset; identifying the technology sends no request beyond that crawl.
- Raw response body:
aria-label="Loading ComfyUI" - Favicon fingerprint:
316510273,1554526046

