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.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - 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. (CVE-2026-114135)

Note that Nessus relies on the presence of the package as reported by the vendor.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - 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. (CVE-2026-114135)

ID	Name	Product	Family	Type	Severity
370943	Linux Distros Unpatched Vulnerability : CVE-2026-114135	Nessus	Misc.	Local	high
476861	SCA: security update for jupyter-server (GHSA-354v-3q48-cv69)	Tenable Cloud Security	SCA Checks	Local	high
476861	SCA: security update for jupyter-server (GHSA-354v-3q48-cv69)	Tenable Self-Hosted Container Security	SCA Checks	Local	high

Detections

Analytics

CVE-2026-114135

high

Tenable Plugins

high

high

high