---
id: CVE-2026-87011
title: >-
  Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI
  platform
summary: >-
  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 doc…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-405
  - CWE-770
vendor: openwebui
product: open_webui
affected:
  - 'open_webui >= 0.9.0, < 0.11.1'
patched:
  - open_webui 0.11.1
published: '2026-09-09'
updated: '2026-09-15'
sourceUpdated: '2026-09-15T16:26:18.880'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-87011'
references:
  - url: >-
      https://github.com/open-webui/open-webui/commit/aeda6ff13a25d3b3ba1b303609f35382db22142c
    label: security-advisories@github.com
  - url: 'https://github.com/open-webui/open-webui/releases/tag/v0.11.1'
    label: security-advisories@github.com
  - url: >-
      https://github.com/open-webui/open-webui/security/advisories/GHSA-3g9q-v48f-hh9w
    label: security-advisories@github.com
  - url: >-
      https://github.com/open-webui/open-webui/security/advisories/GHSA-3g9q-v48f-hh9w
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
epss: 0.00644
epssPercentile: 0.48605
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-14T13:41:36.439676Z'
ingestedAt: '2026-09-14T15:18:19.016Z'
---

## Overview

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.

## Affected

- `open_webui >= 0.9.0, < 0.11.1`

## Remediation

Upgrade past the affected range:

- `open_webui 0.11.1`