When get_image_data returns (None, None) due to an SSRF block (e.g., ComfyUI on private IP like 192.168.x.x), upload_image crashes with 'NoneType' object has no attribute 'lower' in mimetypes.guess_extension.
This is a regression from PR #24518 which added validate_url() to prevent SSRF attacks. While the security fix is important, it broke ComfyUI deployments on private networks.
Fix
Add a null-check at the start of upload_image that raises a descriptive HTTPException pointing users to the ENABLE_RAG_LOCAL_WEB_FETCH workaround.
Changes
backend/open_webui/routers/images.py: Added null-check in upload_image() function
Testing
Verified that upload_image now raises a 400 error with a helpful message instead of crashing
The error message guides users to set ENABLE_RAG_LOCAL_WEB_FETCH=true
🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.
## 📋 Pull Request Information
**Original PR:** https://github.com/open-webui/open-webui/pull/24672
**Author:** [@mturac](https://github.com/mturac)
**Created:** 5/13/2026
**Status:** ❌ Closed
**Base:** `dev` ← **Head:** `fix/comfyui-image-upload-crash`
---
### 📝 Commits (10+)
- [`fe6783c`](https://github.com/open-webui/open-webui/commit/fe6783c16699911c7be17392596d579333fb110c) Merge pull request #19030 from open-webui/dev
- [`fc05e0a`](https://github.com/open-webui/open-webui/commit/fc05e0a6c5d39da60b603b4d520f800d6e36f748) Merge pull request #19405 from open-webui/dev
- [`e3faec6`](https://github.com/open-webui/open-webui/commit/e3faec62c58e3a83d89aa3df539feacefa125e0c) Merge pull request #19416 from open-webui/dev
- [`9899293`](https://github.com/open-webui/open-webui/commit/9899293f050ad50ae12024cbebee7e018acd851e) Merge pull request #19448 from open-webui/dev
- [`140605e`](https://github.com/open-webui/open-webui/commit/140605e660b8186a7d5c79fb3be6ffb147a2f498) Merge pull request #19462 from open-webui/dev
- [`6f1486f`](https://github.com/open-webui/open-webui/commit/6f1486ffd0cb288d0e21f41845361924e0d742b3) Merge pull request #19466 from open-webui/dev
- [`d95f533`](https://github.com/open-webui/open-webui/commit/d95f533214e3fe5beb5e41ec1f349940bc4c7043) Merge pull request #19729 from open-webui/dev
- [`a727153`](https://github.com/open-webui/open-webui/commit/a7271532f8a38da46785afcaa7e65f9a45e7d753) 0.6.43 (#20093)
- [`6adde20`](https://github.com/open-webui/open-webui/commit/6adde203cd292a9e3af9c64a2ae36b603fed096a) Merge pull request #20394 from open-webui/dev
- [`f9b0534`](https://github.com/open-webui/open-webui/commit/f9b0534e0c442631d1cb7205169588b9b6204179) Merge pull request #20522 from open-webui/dev
### 📊 Changes
**1 file changed** (+10 additions, -0 deletions)
<details>
<summary>View changed files</summary>
📝 `backend/open_webui/routers/images.py` (+10 -0)
</details>
### 📄 Description
## Contributor License Agreement
By submitting this pull request, I confirm that I have read and agree to the [Contributor License Agreement](https://github.com/open-webui/open-webui/blob/main/CLA.md).
---
## Summary
When `get_image_data` returns `(None, None)` due to an SSRF block (e.g., ComfyUI on private IP like `192.168.x.x`), `upload_image` crashes with `'NoneType' object has no attribute 'lower'` in `mimetypes.guess_extension`.
This is a regression from PR #24518 which added `validate_url()` to prevent SSRF attacks. While the security fix is important, it broke ComfyUI deployments on private networks.
## Fix
Add a null-check at the start of `upload_image` that raises a descriptive `HTTPException` pointing users to the `ENABLE_RAG_LOCAL_WEB_FETCH` workaround.
## Changes
- `backend/open_webui/routers/images.py`: Added null-check in `upload_image()` function
## Testing
- Verified that `upload_image` now raises a 400 error with a helpful message instead of crashing
- The error message guides users to set `ENABLE_RAG_LOCAL_WEB_FETCH=true`
## Related
- Regression from #24518
- Workaround: Set `ENABLE_RAG_LOCAL_WEB_FETCH=true`
Fixes #24565
---
<sub>🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.</sub>
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📋 Pull Request Information
Original PR: https://github.com/open-webui/open-webui/pull/24672
Author: @mturac
Created: 5/13/2026
Status: ❌ Closed
Base:
dev← Head:fix/comfyui-image-upload-crash📝 Commits (10+)
fe6783cMerge pull request #19030 from open-webui/devfc05e0aMerge pull request #19405 from open-webui/deve3faec6Merge pull request #19416 from open-webui/dev9899293Merge pull request #19448 from open-webui/dev140605eMerge pull request #19462 from open-webui/dev6f1486fMerge pull request #19466 from open-webui/devd95f533Merge pull request #19729 from open-webui/deva7271530.6.43 (#20093)6adde20Merge pull request #20394 from open-webui/devf9b0534Merge pull request #20522 from open-webui/dev📊 Changes
1 file changed (+10 additions, -0 deletions)
View changed files
📝
backend/open_webui/routers/images.py(+10 -0)📄 Description
Contributor License Agreement
By submitting this pull request, I confirm that I have read and agree to the Contributor License Agreement.
Summary
When
get_image_datareturns(None, None)due to an SSRF block (e.g., ComfyUI on private IP like192.168.x.x),upload_imagecrashes with'NoneType' object has no attribute 'lower'inmimetypes.guess_extension.This is a regression from PR #24518 which added
validate_url()to prevent SSRF attacks. While the security fix is important, it broke ComfyUI deployments on private networks.Fix
Add a null-check at the start of
upload_imagethat raises a descriptiveHTTPExceptionpointing users to theENABLE_RAG_LOCAL_WEB_FETCHworkaround.Changes
backend/open_webui/routers/images.py: Added null-check inupload_image()functionTesting
upload_imagenow raises a 400 error with a helpful message instead of crashingENABLE_RAG_LOCAL_WEB_FETCH=trueRelated
ENABLE_RAG_LOCAL_WEB_FETCH=trueFixes #24565
🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.