Medium 4.3Published Sep 9, 2026

CVE-2026-87994Open WebUI: Channel members can overwrite another member's message via the chat completions endpoint

Updated under an hour ago (2026-10-19 10:20 UTC)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for open-webui

Exploited in the last 30 days

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: 4.3 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Weakness (CWE): CWE-639, CWE-862
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Sep 10, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

open-webui open-webui open_webui:open_webui (from the name)	from 0.9.5, < 0.11.1	CNA record
openwebui open_webui openwebui:open_webui	from 0.9.5 before 0.11.1	NVD

References

https://github.com/open-webui/open-webui/security/advisories/GHSA-fmqh-xp37-5hr8x-refsource-confirm, exploit, vendor-advisory
https://github.com/open-webui/open-webui/pull/28631x-refsource-misc, issue-tracking, patch
https://github.com/open-webui/open-webui/commit/7d392bedc9c1aaecc94509a58e59186b614433dcx-refsource-misc, patch
https://github.com/open-webui/open-webui/releases/tag/v0.11.1x-refsource-misc, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.