{"cve":"CVE-2026-114135","nvd":{"published":"2026-10-21T20:17:25.407","modified":"2026-10-22T17:21:57.293","status":"Awaiting Analysis","description":"Jupyter Server is the backend for Jupyter web applications. From 2.0.0 until 2.6.0, enabling GatewayClient.url replaced the normal KernelWebsocketHandler with WebSocketChannelsHandler, which authenticated the user but did not call authorizer.is_authorized(...) for the execute action on the kernels resource. A restricted authenticated user could therefore open an upstream kernel channel and obtain kernel execution despite the configured Authorizer denying that action, exposing data and credentials available to the kernel and permitting modification or disruption of the kernel environment. The default gateway configuration is fixed in version 2.6.0. In 2.6.0 and later, the same authorization bypass remains possible when a deployment manually registers the deprecated jupyter_server.gateway.handlers module, because its handler still omits the configured kernel-execute authorization decision.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":8.8},"cwes":["CWE-862"],"references":["https://github.com/jupyter-server/jupyter_server/commit/35ffe5d435682128da16dc144a8e9e9f8fa85dd8","https://github.com/jupyter-server/jupyter_server/pull/1261","https://github.com/jupyter-server/jupyter_server/releases/tag/v2.6.0","https://github.com/jupyter-server/jupyter_server/security/advisories/GHSA-354v-3q48-cv69"],"products":[],"source":"nvd","synced_at":"2026-10-23T16:39:28.036610720+00:00"},"epss":{"cve":"CVE-2026-114135","score":0.00484,"percentile":0.4141,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-354v-3q48-cv69","url":"https://osv.dev/vulnerability/GHSA-354v-3q48-cv69","summary":"Jupyter Server: Gateway WebSocket handler bypasses kernel execute authorization","modified":"2026-10-22T16:00:09.146840746Z","packages":[{"ecosystem":"PyPI","name":"jupyter-server","purl":"pkg:pypi/jupyter-server","ranges":[">=2.0.0 <2.6.0"],"fixed":["2.6.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}