CVE-2026-33709 json
JupyterHub has an Open Redirect Vulnerability
published 7mo ago modified 2mo ago also BIT-jupyterhub-2026-33709 , EUVD-2026-18880 , GHSA-3vff-hjqv-m7h8 , PYSEC-2026-2188
- cvss
- 6.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 11%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- pypi jupyterhub 5.4.4
- bitnami jupyterhub 5.4.4
- jupyter jupyterhub 5.4.4
Is CVE-2026-33709 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 7mo ago
Exploit prediction
0.21% chance of exploitation in the next 30 days, higher than 11% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.1 | 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 |
| GitHub | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| CNA | 4.0 | 5.1 | 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| NVD | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| OSV | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | jupyterhub | <5.4.4 |
5.4.4 |
| bitnami | jupyterhub | <5.4.4 |
5.4.4 |
Affected products
- jupyterhub jupyterhub
Classification
- Weakness
-
- CWE-601 URL Redirection to Untrusted Site
References
-
github.com
/jupyterhub/jupyterhub/security/advisories/GHSA-3vff-hjqv-m7h8
web, mitigation, vendor-advisory, advisory
-
github.com
/jupyterhub/jupyterhub/releases/tag/5.4.4
web, product
-
nvd.nist.gov
/vuln/detail/CVE-2026-33709
advisory, web
-
github.com
/jupyterhub/jupyterhub
package
Sources
- CVE List CVE-2026-33709
- GitHub Advisory GHSA-3vff-hjqv-m7h8
- NVD CVE-2026-33709
- OSV BIT-jupyterhub-2026-33709
- OSV PYSEC-2026-2188
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.