Jupyter Server is the backend for Jupyter web applications. In versions 2.17.0 and earlier, the secret used to sign authentication cookies is persisted to a static file at ~/.local/share/jupyter/runtime/jupyter_cookie_secret and is never rotated when a user changes their password. After a password reset and server restart, any previously issued authentication cookie remains cryptographically valid because the signing key has not changed. An attacker who has captured a session cookie through any means retains full authenticated access to the server regardless of subsequent password changes. This affects deployments using password-based authentication, particularly shared or public-facing servers where credential rotation is expected to revoke existing sessions. This issue has been fixed in version 2.18.0.

The remote Fedora 44 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-dd1d19e58b advisory.

    New version fixing high-severity CVE.

    ----

    New version of jupyter-server fixing various security vulnerabilities.


Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Fedora 43 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-9536c7cb79 advisory.

    New version of jupyter-server fixing various security vulnerabilities.

Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

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

  - Jupyter Server is the backend for Jupyter web applications. In versions 2.17.0 and earlier, the secret
    used to sign authentication cookies is persisted to a static file at
    ~/.local/share/jupyter/runtime/jupyter_cookie_secret and is never rotated when a user changes their
    password. After a password reset and server restart, any previously issued authentication cookie remains
    cryptographically valid because the signing key has not changed. An attacker who has captured a session
    cookie through any means retains full authenticated access to the server regardless of subsequent password
    changes. This affects deployments using password-based authentication, particularly shared or public-
    facing servers where credential rotation is expected to revoke existing sessions. This issue has been
    fixed in version 2.18.0. (CVE-2026-40934)

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. In versions 2.17.0 and earlier, the secret     used to sign authentication cookies is persisted to a static file at     ~/.local/share/jupyter/runtime/jupyter_cookie_secret and is never rotated when a user changes their     password. After a password reset and server restart, any previously issued authentication cookie remains     cryptographically valid because the signing key has not changed. An attacker who has captured a session     cookie through any means retains full authenticated access to the server regardless of subsequent password     changes. This affects deployments using password-based authentication, particularly shared or public-     facing servers where credential rotation is expected to revoke existing sessions. This issue has been     fixed in version 2.18.0. (CVE-2026-40934)

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

ID	Name	Product	Family	Type	Severity
325143	Fedora 44 : python-jupyter-server (2026-dd1d19e58b)	Nessus	Fedora Local Security Checks	Local	high
323134	Fedora 43 : python-jupyter-server (2026-9536c7cb79)	Nessus	Fedora Local Security Checks	Local	high
441556	SCA: security update for jupyter-server (GHSA-5mrq-x3x5-8v8f)	Tenable Cloud Security	SCA Checks	Local	high
441556	SCA: security update for jupyter-server (GHSA-5mrq-x3x5-8v8f)	Tenable Self-Hosted Container Security	SCA Checks	Local	high
312627	Linux Distros Unpatched Vulnerability : CVE-2026-40934	Nessus	Misc.	Local	high

Detections

Analytics

CVE-2026-40934

high

Tenable Plugins

high

high

high

high

high