CVE-2026-87011
Open WebUI: Unauthenticated requests can stall the server via uncached OIDC fetches in back-channel logout
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.0 until 0.11.1, the unauthenticated POST /oauth/backchannel-logout handler in backend/open_webui/utils/oauth.py fetched the OIDC discovery document and signing keys before validating a submitted logout token. Each request repeated uncached network fetches, and the signing-key lookup blocked the async event loop, so requests carrying invalid tokens could stall the single-worker instance and amplify traffic to the identity provider when ENABLE_OAUTH_BACKCHANNEL_LOGOUT was enabled. This issue is fixed in version 0.11.1.
| CWE | CWE-405 CWE-770 |
| Vendor | open-webui |
| Product | open-webui |
| Published | Sep 9, 2026 |
| Last Updated | Sep 14, 2026 |
Get instant alerts for open-webui open-webui
Be the first to know when new high vulnerabilities affecting open-webui open-webui are published — delivered to Slack, Telegram or Discord.
CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H