{"schema_version": "1.6.1", "id": "CVE-2026-82438", "summary": "Authenticated API Responses Exposed to Arbitrary Web Origins", "details": "Description\n\nThree separate mechanisms allowed a web page on an unrelated origin to read responses that Storm's HTTP\ncomponents served to an authenticated user.\n\nThe Logviewer reflected the request's `Origin` header back in `Access-Control-Allow-Origin` while also\nsending `Access-Control-Allow-Credentials: true`. The published security model documents a permissive\n`Access-Control-Allow-Origin: *` posture as accepted, which is safe precisely because browsers refuse to\nhonour `*` together with credentials; reflecting the concrete origin removes that protection.\n\nThe shared CORS filter used by the UI, the Logviewer and DRPC was configured with a response header name\nwhere an initialisation parameter name was expected. The container ignored the setting and applied its own\ndefaults, which allow credentials.\n\nFinally, the UI and Logviewer wrapped API responses in a caller-supplied JSONP callback for every GET\nrequest. A script element on any origin can load such a response, which bypasses the same-origin policy\nentirely rather than negotiating it, and there was no way to turn the behaviour off.\n\nIn each case the effect is that a page visited by an authenticated operator can read cluster, topology and\nlog data on their behalf.\n\nMitigation\n\nUpgrade to 3.1.0, where the Logviewer no longer reflects the request origin in a credentialed response, the\nCORS filter is configured explicitly, and JSONP wrapping is governed by `ui.enable.jsonp`, which defaults to\nfalse.\n\nNote that disabling JSONP is a behaviour change for tooling that passes a `callback` query parameter; such\ntooling should be moved to ordinary JSON requests.\n\nUsers who cannot upgrade immediately should place the UI, Logviewer and DRPC HTTP endpoints behind a reverse\nproxy that strips `Access-Control-Allow-Origin` and `Access-Control-Allow-Credentials` from responses and\nrejects requests carrying a `callback` parameter.\n\nCredit\n\nThe ASF -- found using Claude agents to study the security of open-source projects, validated and reported by Apache Storm.", "affected": [{"ranges": [{"type": "SEMVER", "events": [{"introduced": "3.0.0"}, {"fixed": "3.1.0"}]}]}], "references": [{"type": "WEB", "url": "https://lists.apache.org/thread/2o7tl3hcdd865njxsn4d9cxp1frkctz3"}]}