{"cve":"CVE-2026-33709","nvd":{"published":"2026-04-03T22:16:26.657","modified":"2026-07-24T22:10:00.140","status":"Analyzed","description":"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_v4":{"vector":"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","score":5.1},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","score":6.1},"cwes":["CWE-601"],"references":["https://github.com/jupyterhub/jupyterhub/releases/tag/5.4.4","https://github.com/jupyterhub/jupyterhub/security/advisories/GHSA-3vff-hjqv-m7h8"],"products":["jupyter:jupyterhub"],"source":"nvd","synced_at":"2026-10-19T22:28:59.047572785+00:00"},"epss":{"cve":"CVE-2026-33709","score":0.00214,"percentile":0.11785,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-3vff-hjqv-m7h8","url":"https://osv.dev/vulnerability/GHSA-3vff-hjqv-m7h8","summary":"JupyterHub has an Open Redirect Vulnerability","modified":"2026-07-13T07:26:28.413653255Z","packages":[{"ecosystem":"PyPI","name":"jupyterhub","purl":"pkg:pypi/jupyterhub","ranges":["<5.4.4"],"fixed":["5.4.4"]}]},{"id":"PYSEC-2026-2188","url":"https://osv.dev/vulnerability/PYSEC-2026-2188","summary":"","modified":"2026-07-13T07:26:28.413653255Z","packages":[{"ecosystem":"PyPI","name":"jupyterhub","purl":"pkg:pypi/jupyterhub","ranges":["<5.4.4"],"fixed":["5.4.4"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}