PYSEC-2026-4117 Open WebUI: Unauthenticated requests can stall the server via uncached OIDC fetches in back-channel logout

Summary The OIDC back-channel logout endpoint is unauthenticated by design, because the identity provider calls it without a browser session. Before checking whether the submitted logout token was genuine, the handler fetched the provider's discovery document and its signing keys over the network...

PT-2026-105866

Summary The OIDC back-channel logout endpoint is unauthenticated by design, because the identity provider calls it without a browser session. Before checking whether the submitted logout token was genuine, the handler fetched the provider's discovery document and its signing keys over the network...

CVE-2026-87011

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/openwebui/utils/oauth.py fetched the OIDC discovery document and signing keys before validating a submitted logout...

CVE-2026-87011

Open WebUI , a self-hosted AI platform, contains a denial-of-service vulnerability in the unauthenticated POST /oauth/backchannel-logout handler (backend/open_webui/utils/oauth.py). From version 0.9.0 through 0.11.1 , the handler fetched the OIDC discovery document and signing keys before validat...

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/openwebui/utils/oauth.py fetched the OIDC discovery document and signing keys before validating a submitted logout...

CVE-2026-87011: Asymmetric Resource Consumption (Amplification)

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/openwebui/utils/oauth.py fetched the OIDC discovery document and signing keys before validating a submitted logout...

PYSEC-2026-3596 Open WebUI: ReDoS in skill-mention regexes causes whole-instance DoS on default config

Summary Two regexes in backend/openwebui/utils/middleware.py that parse skill-mention tags backtrack in On² on input that contains . Both run synchronously, on the asyncio event loop, on every chat completion with no feature gate. Because the default deployment is a single uvicorn worker, one suc...