CVE-2026-87994
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform.
Does this matter?
Lower severity and a low EPSS score (0.21%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 3.1
- 4.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
- EPSS
- 0.21% probability · 12th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-639, CWE-862
- Source
- security-advisories@github.com
References
- 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
- https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8
- https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.