Not a U.S. government website. NDD is an independent vulnerability database by Volerion and is not affiliated with or endorsed by NIST or NVD.

CVE-2026-87011 Details

Description

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.

Metrics

CVSS 3.x Severity and Vector Strings:

CNA: [email protected]CVSS-B:7.5 HIGHVector:CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.

URL	Source(s)	Tag(s)
https://github.com/open-webui/open-webui/security/advisories/GHSA-3g9q-v48f-hh9w	CISA-ADP	ExploitVendor Advisory
https://github.com/open-webui/open-webui/commit/aeda6ff13a25d3b3ba1b303609f35382db22142c	[email protected]	Patch
https://github.com/open-webui/open-webui/releases/tag/v0.11.1	[email protected]	Release Notes
https://github.com/open-webui/open-webui/security/advisories/GHSA-3g9q-v48f-hh9w	[email protected]	ExploitVendor Advisory

Weakness Enumeration

CWE-ID	CWE Name	Source
CWE-405	Asymmetric Resource Consumption (Amplification)	[email protected]
CWE-770	Allocation of Resources Without Limits or Throttling	[email protected]

Affected Products

Product	Versions
openwebui open webui	>= 0.9.0, < 0.11.1
CPE cpe:2.3:a:openwebui:open_webui:::::::: Remediation No remediation found in references.

Change History

3 change records found show changes

Date	Action	Recorded By
Sep 15, 2026	Initial Analysis	[email protected]
Sep 14, 2026	CVE Modified	CISA-ADP
Sep 9, 2026	New CVE Received	[email protected]