CVE-2026-33709
MEDIUM6.1EPSS 0.01%JupyterHub has an Open Redirect Vulnerability
Published: 4/3/2026Modified: 5/5/2026
Description
## 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.
Affected packages (3)
- Bitnami/jupyterhubfrom 0, < 5.4.4
- Debian/jupyterhubfrom 0
- PyPI/jupyterhubfrom 0, < 5.4.4
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N |
| osv | CVSS 3.1 | MEDIUM6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
References (5)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2026-33709
- ADVISORYhttps://security-tracker.debian.org/tracker/CVE-2026-33709
- PATCHhttps://github.com/jupyterhub/jupyterhub
- WEBhttps://github.com/jupyterhub/jupyterhub/releases/tag/5.4.4
- WEBhttps://github.com/jupyterhub/jupyterhub/security/advisories/GHSA-3vff-hjqv-m7h8