EUVD-2026-75170
GHSA-3g9q-v48f-hh9w
Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Endpoint is network-accessible and unauthenticated; once backchannel logout is enabled no additional attack complexity exists, and impact is availability-only.
Primary rating from Vendor (GitHub_M).
CVSS VectorVendor: GitHub_M
Lifecycle Timeline
6DescriptionCVE.org
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.
AnalysisAI
Denial of service in Open WebUI versions 0.9.0-0.11.0 allows unauthenticated remote attackers to stall the application server and amplify traffic to the configured identity provider by submitting requests to the backchannel-logout OAuth endpoint. The handler fetches the OIDC discovery document and signing keys on every inbound request-including invalid ones-before performing any token validation; additionally, the original synchronous PyJWKClient call blocks the asyncio event loop, so each malicious request can render the single-worker instance unresponsive. …
Unlock full vulnerability intelligence
- Risk assessment & exploitation conditions
- Attack chain visualization
- Remediation with exact patch versions
- Threat intelligence from 22 sources
- Personal watchlist & email alerts
Free forever · No credit card required
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | The attack requires ENABLE_OAUTH_BACKCHANNEL_LOGOUT to be explicitly set to true in the Open WebUI configuration-this requires the operator to have configured an OIDC OAuth integration and enabled backchannel logout support, which is not a default setting. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 7.5 score (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) reflects a pure availability-impact denial of service with no authentication barrier on the vulnerable endpoint. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | Full exploit scenario with step-by-step reproduction available after sign-in. |
| Remediation | Vendor-released patch: v0.11.1. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours, identify all instances of Open WebUI in your environment and document which versions are deployed, prioritizing those visible to the internet or integrated with production identity providers. …
Sign in for detailed remediation steps and compensating controls.
Threat intelligence, references, and detailed analysis are available after sign-in.
More in Open Webui
View allA vulnerability in open-webui/open-webui version 0.3.8 allows an attacker with a user-level account to perform a session
An XSS vulnerability exists in open-webui/open-webui versions <= 0.3.8, specifically in the function that constructs the
A Stored Cross-Site Scripting (XSS) vulnerability exists in the chat file upload functionality of open-webui/open-webui
A vulnerability in open-webui/open-webui versions <= 0.3.8 allows remote code execution by non-admin users via Cross-Sit
Attacker controlled files can be uploaded to arbitrary locations on the web server's filesystem by abusing a path traver
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.6.37, a St
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.6.37, a Se
A stored cross-site scripting (XSS) vulnerability exists in open-webui/open-webui version 0.3.8. Rated high severity (CV
In version v0.3.10 of open-webui/open-webui, the `api/v1/utils/pdf` endpoint lacks authentication mechanisms, allowing u
In open-webui version 0.3.8, the endpoint `/models/upload` is vulnerable to arbitrary file write due to improper handlin
The `/openai/models` endpoint in open-webui/open-webui version 0.3.8 is vulnerable to Server-Side Request Forgery (SSRF)
In version 0.3.32 of open-webui/open-webui, the absence of authentication mechanisms allows any unauthenticated attacker
Share
External POC / Exploit Code
Leaving vuln.today