What’s Vulnerable › Vulnerabilities

CVE-2026-87997: Open WebUI: Any authenticated user can inject chats into another user's folder via chat completions

• Severity: medium (CVSS 4.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-09-09 · updated 2026-09-16
• Weakness: CWE-639

Description

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.

Affected products

• open-webui: from 0.10.0 before 0.11.1 — fixed in 0.11.1

How to fix

Upgrade to a fixed version: open-webui 0.11.1. Check the vendor advisory for mitigations.

References

• https://github.com/open-webui/open-webui/commit/d9e23b90c100d19b00270aea3cde0501d2354a6c
• https://github.com/open-webui/open-webui/pull/28366
• https://github.com/open-webui/open-webui/releases/tag/v0.11.1
• https://github.com/open-webui/open-webui/security/advisories/GHSA-3pf7-q2g3-wj28
• https://github.com/open-webui/open-webui/security/advisories/GHSA-3pf7-q2g3-wj28

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