Channel messages are user-authored and must never reach the allow-scripts iframe path used for assistant tool-call rendering.
Frontend: thread an untrustedSource flag from channel Message.svelte through Markdown -> MarkdownTokens -> ConsecutiveDetailsGroup. When true, allEmbeds is forced to an empty array, skipping iframe rendering entirely. Assistant chat messages are unaffected (default is false).
Backend (defense-in-depth): strip
blocks from channel message content in new_message_handler and update_message_by_id before persistence.
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Deleting the CLA section will lead to immediate closure of your PR and it will not be merged in.
🔄 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/24387
**Author:** [@Classic298](https://github.com/Classic298)
**Created:** 5/5/2026
**Status:** 🔄 Open
**Base:** `dev` ← **Head:** `fix/stored-xss-channel-messages`
---
### 📝 Commits (1)
- [`3659ff9`](https://github.com/open-webui/open-webui/commit/3659ff9267cc65e204731c0ad4c1d908b055817c) fix: prevent stored XSS via tool_calls details in channel messages
### 📊 Changes
**5 files changed** (+40 additions, -1 deletions)
<details>
<summary>View changed files</summary>
📝 `backend/open_webui/routers/channels.py` (+25 -0)
📝 `src/lib/components/channel/Messages/Message.svelte` (+2 -0)
📝 `src/lib/components/chat/Messages/Markdown.svelte` (+3 -0)
📝 `src/lib/components/chat/Messages/Markdown/ConsecutiveDetailsGroup.svelte` (+7 -1)
📝 `src/lib/components/chat/Messages/Markdown/MarkdownTokens.svelte` (+3 -0)
</details>
### 📄 Description
Channel messages are user-authored and must never reach the allow-scripts iframe path used for assistant tool-call rendering.
Frontend: thread an untrustedSource flag from channel Message.svelte through Markdown -> MarkdownTokens -> ConsecutiveDetailsGroup. When true, allEmbeds is forced to an empty array, skipping iframe rendering entirely. Assistant chat messages are unaffected (default is false).
Backend (defense-in-depth): strip <details type=tool_calls> blocks from channel message content in new_message_handler and update_message_by_id before persistence.
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- [X] By submitting this pull request, I confirm that I have read and fully agree to the [Contributor License Agreement (CLA)](https://github.com/open-webui/open-webui/blob/main/CONTRIBUTOR_LICENSE_AGREEMENT), and I am providing my contributions under its terms.
> [!NOTE]
> Deleting the CLA section will lead to immediate closure of your PR and it will not be merged in.
---
<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/24387
Author: @Classic298
Created: 5/5/2026
Status: 🔄 Open
Base:
dev← Head:fix/stored-xss-channel-messages📝 Commits (1)
3659ff9fix: prevent stored XSS via tool_calls details in channel messages📊 Changes
5 files changed (+40 additions, -1 deletions)
View changed files
📝
backend/open_webui/routers/channels.py(+25 -0)📝
src/lib/components/channel/Messages/Message.svelte(+2 -0)📝
src/lib/components/chat/Messages/Markdown.svelte(+3 -0)📝
src/lib/components/chat/Messages/Markdown/ConsecutiveDetailsGroup.svelte(+7 -1)📝
src/lib/components/chat/Messages/Markdown/MarkdownTokens.svelte(+3 -0)📄 Description
Channel messages are user-authored and must never reach the allow-scripts iframe path used for assistant tool-call rendering.
Frontend: thread an untrustedSource flag from channel Message.svelte through Markdown -> MarkdownTokens -> ConsecutiveDetailsGroup. When true, allEmbeds is forced to an empty array, skipping iframe rendering entirely. Assistant chat messages are unaffected (default is false).
Backend (defense-in-depth): strip
Contributor License Agreement
🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.