| Component | Open WebUI |
| Severity | medium (CVSS 4.3) |
| CVSS vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N |
| Published (NVD) | 2026-09-09 |
| Last modified | 2026-09-16 |
| Affected versions | open_webui >= 0.9.5, < 0.11.1 |
| Fixed in | 0.11.1 |
| Weakness | CWE-639CWE-862 |
| CISA KEV | not listed |
NVD description
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.5 until 0.11.1, the channel branch of chat_completion in backend/open_webui/main.py checked channel write access and channel membership for a supplied message_id but did not verify that the calling user authored the targeted message. A channel member could use the chat completions endpoint to replace another member's message while preserving the victim as the stored author, altering the conversation record without gaining access to other channels. This issue is fixed in version 0.11.1.
What to do
- Upgrade Open WebUI to
0.11.1or later. - Do not expose the component's API or UI to the internet without authentication in front of it.
Sources
- NVD: CVE-2026-87994
- https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8
- https://github.com/open-webui/open-webui/commit/7d392bedc9c1aaecc94509a58e59186b614433dc
- https://github.com/open-webui/open-webui/pull/28631
- https://github.com/open-webui/open-webui/releases/tag/v0.11.1
Read more
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