{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-87011","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-09-08T16:44:23.783Z","datePublished":"2026-09-09T20:54:26.207Z","dateUpdated":"2026-09-09T20:54:26.207Z"},"containers":{"cna":{"title":"Open WebUI: Unauthenticated requests can stall the server via uncached OIDC fetches in back-channel logout","problemTypes":[{"descriptions":[{"cweId":"CWE-405","lang":"en","description":"CWE-405: Asymmetric Resource Consumption (Amplification)","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-770","lang":"en","description":"CWE-770: Allocation of Resources Without Limits or Throttling","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"references":[{"name":"https://github.com/open-webui/open-webui/security/advisories/GHSA-3g9q-v48f-hh9w","tags":["x_refsource_CONFIRM"],"url":"https://github.com/open-webui/open-webui/security/advisories/GHSA-3g9q-v48f-hh9w"},{"name":"https://github.com/open-webui/open-webui/commit/aeda6ff13a25d3b3ba1b303609f35382db22142c","tags":["x_refsource_MISC"],"url":"https://github.com/open-webui/open-webui/commit/aeda6ff13a25d3b3ba1b303609f35382db22142c"},{"name":"https://github.com/open-webui/open-webui/releases/tag/v0.11.1","tags":["x_refsource_MISC"],"url":"https://github.com/open-webui/open-webui/releases/tag/v0.11.1"}],"affected":[{"vendor":"open-webui","product":"open-webui","versions":[{"version":">= 0.9.0, < 0.11.1","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-09-09T20:54:26.207Z"},"descriptions":[{"lang":"en","value":"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."}],"source":{"advisory":"GHSA-3g9q-v48f-hh9w","discovery":"UNKNOWN"}}}}