Openwebui Open Webui
CVE-2026-87997
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.10.0 until 0.11.1, POST /api/chat/completions and POST /api/v1/chat/completions in backend/open_webui/main.py copied a client-supplied folder_id into a new chat without applying the folder write-access check used by the dedicated chat routes. An authenticated user who knew a shared folder identifier could inject an attacker-controlled chat into a folder where the user had read-only or no write access, causing the entry to appear to authorized folder readers. This issue is fixed in version 0.11.1.
What this means for your business
- It affects Openwebui Open Webui. It matters if your company, or a supplier that handles your data, runs it.
- Code showing how to exploit it has been published, but real attacks have not been confirmed.
- An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
What to do
- 1Check whether your company or your suppliers run Openwebui Open Webui, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
Not sure if your company is exposed?
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Scoring
- CVSS
- 4.3 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N- Weakness
- CWE-639
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-09-09
- Last modified
- 2026-09-16
- Sources
- NVD
Affected products
- Openwebui Open Webui0.10.0 - 0.11.1
As listed in the NVD configuration data. Not a statement about your estate.