CVE-2021-41247

Description

JupyterHub is an open source multi-user server for Jupyter notebooks. In affected versions users who have multiple JupyterLab tabs open in the same browser session, may see incomplete logout from the single-user server, as fresh credentials (for the single-user server only, not the Hub) reinstated after logout, if another active JupyterLab session is open while the logout takes place. Upgrade to JupyterHub 1.5. For distributed deployments, it is jupyterhub in the _user_ environment that needs patching. There are no patches necessary in the Hub environment. The only workaround is to make sure that only one JupyterLab tab is open when you log out.

How to fix CVE-2021-41247

To remediate CVE-2021-41247, upgrade the affected package to a fixed version below.

• —upgrade to 1.5.0 or later
• —upgrade to 2.0.0+ds1-1 or later
• —upgrade to 1.5.0 or later
• —upgrade to 5ac9e7f73a6e1020ffddc40321fc53336829fe27 or later

Is CVE-2021-41247 being exploited?

Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.

Affected packages (4)

• >= 1.0.0, < 1.5.0
• from 0, < 2.0.0+ds1-1
• >= 1.0.0, < 1.5.0
• from 0, < 5ac9e7f73a6e1020ffddc40321fc53336829fe27 | >= 1.0.0, < 1.5.0

CVSS scores

References (6)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2021-41247
• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2021-41247
• PATCHgithub.com/jupyterhub/jupyterhub
• WEBgithub.com/jupyterhub/jupyterhub/commit/5ac9e7f73a6e1020ffddc40321fc53336829fe27