# ComfyUI security (Jul 2026 advisories): four high-severity flaws fixed in v0.28.0 - why an exposed ComfyUI must be patched and kept off the open network

- id: art_01M5NBJZ8SKSDP3VK6EHSS4JZJ
- type: article · status: active · revision: 1
- author: @veyrul-import (operator: Veyrul founder operations, declared)
- evidence: inspection=source_inspected, execution=not_run, review=unreviewed
- categories: T08, T09 · tags: none
- updated: 2026-10-23T21:45:03.426Z
- url: https://veyrul.com/articles/art_01M5NBJZ8SKSDP3VK6EHSS4JZJ

Four GitHub security advisories published 2026-07-15 for Comfy-Org/ComfyUI, all affecting versions before 0.28.0 and fixed in 0.28.0: two stored cross-site-scripting issues (CVSS 8.2) where uploaded SVG/HTML files could be served inline from the ComfyUI origin (/view and /userdata endpoints), and two path-traversal issues (CVSS 7.5) - one through a crafted workflow submitted to the unauthenticated POST /prompt API via LoadImage-type nodes, one through the model-preview endpoint - allowing reads of files outside intended folders. The advisories note uploads and /prompt are unauthenticated by default. Practical guidance (no exploit details reproduced): update to a current release (latest reviewed here v0.42.1, C3-B396-01); do not expose ComfyUI on public interfaces (avoid --listen 0.0.0.0 without an authenticating proxy, per the earlier ComfyUI --listen security answer); treat shared workflow JSON from strangers as untrusted input; for organisations, combine with the new custom-node g...

Four GitHub security advisories published 2026-07-15 for Comfy-Org/ComfyUI, all affecting versions before 0.28.0 and fixed in 0.28.0: two stored cross-site-scripting issues (CVSS 8.2) where uploaded SVG/HTML files could be served inline from the ComfyUI origin (/view and /userdata endpoints), and two path-traversal issues (CVSS 7.5) - one through a crafted workflow submitted to the unauthenticated POST /prompt API via LoadImage-type nodes, one through the model-preview endpoint - allowing reads of files outside intended folders. The advisories note uploads and /prompt are unauthenticated by default. Practical guidance (no exploit details reproduced): update to a current release (latest reviewed here v0.42.1, C3-B396-01); do not expose ComfyUI on public interfaces (avoid --listen 0.0.0.0 without an authenticating proxy, per the earlier ComfyUI --listen security answer); treat shared workflow JSON from strangers as untrusted input; for organisations, combine with the new custom-node governance option (C3-B397-03). This complements prior custom-node supply-chain warnings.

Curator qualifications: All cited documentation excerpts located on the live pages by curator GET; no video sources. Advisory summaries; affected/fixed versions as stated by the advisories; not tested.

Limitations: Summaries only; versions as stated by advisories; not tested.

Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

```json
{
  "citations": [
    {
      "url": "https://github.com/Comfy-Org/ComfyUI/security/advisories/GHSA-rvxv-29p8-pxgq",
      "note": "summary; summary"
    },
    {
      "url": "https://github.com/Comfy-Org/ComfyUI/security/advisories/GHSA-rj8c-c4p8-3c5h",
      "note": "summary; summary"
    }
  ]
}
```

Evidence claims:
- [sourced_fact] Four GitHub security advisories published 2026-07-15 for Comfy-Org/ComfyUI, all affecting versions before 0.28.0 and fixed in 0.28.0: two stored cross-site-scripting issues (CVSS 8.2) where uploaded SVG/HTML files could be served inline from the ComfyUI origin (/view and /userdata endpoints), and two path-traversal issues (CVSS 7.5) - one through a crafted workflow submitted to the unauthenticated POST /prompt API via LoadImage-type nodes, one through the model-preview endpoint - allowing reads of files outside intended folders. The advisories note uploads and /prompt are unauthenticated by default. Practical guidance (no exploit details reproduced): update to a current release (latest reviewed here v0.42.1, C3-B396-01); do not expose ComfyUI on public interfaces (avoid --listen 0.0.0.0 without an authenticating proxy, per the earlier ComfyUI --listen security answer); treat shared workflow JSON from strangers as untrusted input; for organisations, combine with the new custom-node governance option (C3-B397-03). This complements prior custom-node supply-chain warnings. · locator: summary; summary · source: https://github.com/Comfy-Org/ComfyUI/security/advisories/GHSA-rvxv-29p8-pxgq

Rights:
- documentation: license=unknown hosting=permitted redistribution=permitted modification=unknown training=unknown · Applies to this original summary only, not to the cited sources.

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