CVE-2026-33709
mediumpriority · track · 24EPSS 0.002 · 11 %ileEUUSEPSS · scored 2026-10-28
JupyterHub is software that allows one to create a multi-user server for Jupyter notebooks. Prior to version 5.4.4, an open redirect vulnerability in JupyterHub allows attackers to construct links which, when clicked, take users to the JupyterHub login page, after which they are sent to an arbitrary attacker-controlled site outside JupyterHub instead of a JupyterHub page, bypassing JupyterHub's check to prevent this. This issue has been patched in version 5.4.4.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 1.2–6.1
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (4)
Products and version ranges known to be affected.
advisories (3)
Vendor and ecosystem advisories describing this.
- GHSA-3vff-hjqv-m7h8JupyterHub has an Open Redirect Vulnerability2026-04-03ghsa · osvUS
## Affected Version JupyterHub <= 5.4.3 ## Impact An open redirect vulnerability in JupyterHub <=5.4.3 allows attackers to construct links which, when clicked, take users to the JupyterHub login page, after which they are sent to an arbitrary attacker-controlled site outside JupyterHub instead of a JupyterHub page, bypassing JupyterHub's check to prevent this. ## Patches Upgrade to JupyterHub 5.4.4 ## Workarounds A deployment can apply filters on the Location header in a reverse proxy such as nginx/apache/traefik.
- BIT-jupyterhub-2026-33709JupyterHub has an Open Redirect Vulnerability2026-04-08vendor · osvUS
JupyterHub is software that allows one to create a multi-user server for Jupyter notebooks. Prior to version 5.4.4, an open redirect vulnerability in JupyterHub allows attackers to construct links which, when clicked, take users to the JupyterHub login page, after which they are sent to an arbitrary attacker-controlled site outside JupyterHub instead of a JupyterHub page, bypassing JupyterHub's check to prevent this. This issue has been patched in version 5.4.4.
- PYSEC-2026-21882026-04-03vendor · osvUS
JupyterHub is software that allows one to create a multi-user server for Jupyter notebooks. Prior to version 5.4.4, an open redirect vulnerability in JupyterHub allows attackers to construct links which, when clicked, take users to the JupyterHub login page, after which they are sent to an arbitrary attacker-controlled site outside JupyterHub instead of a JupyterHub page, bypassing JupyterHub's check to prevent this. This issue has been patched in version 5.4.4.
also known as (7)
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sources
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references (7)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2026-33709cnnvd
- https://github.com/jupyterhub/jupyterhub/releases/tag/5.4.4cnnvd
- https://github.com/jupyterhub/jupyterhub/security/advisories/GHSA-3vff-hjqv-m7h8cnnvd
- https://github.com/jupyterhub/jupyterhub/releases/tag/5.4.4enisa_euvd
- https://github.com/jupyterhub/jupyterhub/security/advisories/GHSA-3vff-hjqv-m7h8enisa_euvd
- https://github.com/jupyterhub/jupyterhub/releases/tag/5.4.4Productnvd
- https://github.com/jupyterhub/jupyterhub/security/advisories/GHSA-3vff-hjqv-m7h8MitigationVendor Advisorynvd
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