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.
Weakness
According to WASC, “Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization.”
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Jupyter_server | Jupyter | * | 2.18.0 (excluding) |
| Jupyter-server | Ubuntu | questing | * |