CVE-2026-87997CWE-639CWE-862broken-access-control

CVE-2026-87997

Medium · published September 10, 2026

CVSS v3.1
4.3
EPSS
0%
Percentile
29.9
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
4.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00372 · 29.9th percentile
Weaknesses
CWE-639 · Authorization Bypass Through User-Controlled Key; CWE-862 · Missing Authorization
Published
2026-09-10T02:18Z
Affected products (1)
ProductVersionsFixed in
openwebui/open_webui≥ 0.10.0, < 0.11.10.11.1
References (5)
https://github.com/open-webui/open-webui/commit/d9e23b90c100d19b00270aea3cde0501d2354a6c · [email protected]https://github.com/open-webui/open-webui/pull/28366 · [email protected]https://github.com/open-webui/open-webui/releases/tag/v0.11.1 · [email protected]https://github.com/open-webui/open-webui/security/advisories/GHSA-3pf7-q2g3-wj28 · [email protected]https://github.com/open-webui/open-webui/security/advisories/GHSA-3pf7-q2g3-wj28 · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 11 SEP 03:19Z
    EPSS moved — → 0%
    epss
  • 09 SEP 21:30Z
    Open WebUI: Any authenticated user can inject chats into another user's folder via chat completions
    cvelistv5