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GHSA-3VFF-HJQV-M7H8

Vulnerability from github – Published: 2026-04-03 21:36 – Updated: 2026-04-27 16:19
VLAI
Summary
JupyterHub has an Open Redirect Vulnerability
Details

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.

Severity
6.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
5.1 (Medium)
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
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 5.4.3"
      },
      "package": {
        "ecosystem": "PyPI",
        "name": "jupyterhub"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.4.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33709"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-601"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-03T21:36:07Z",
    "nvd_published_at": "2026-04-03T22:16:26Z",
    "severity": "MODERATE"
  },
  "details": "## Affected Version\n\nJupyterHub \u003c= 5.4.3\n\n## Impact\n\nAn open redirect vulnerability in JupyterHub \u003c=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\u0027s check to prevent this.\n\n## Patches\n\nUpgrade to JupyterHub 5.4.4\n\n## Workarounds\n\nA deployment can apply filters on the Location header in a reverse proxy such as nginx/apache/traefik.",
  "id": "GHSA-3vff-hjqv-m7h8",
  "modified": "2026-04-27T16:19:31Z",
  "published": "2026-04-03T21:36:07Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/jupyterhub/jupyterhub/security/advisories/GHSA-3vff-hjqv-m7h8"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33709"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/jupyterhub/jupyterhub"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jupyterhub/jupyterhub/releases/tag/5.4.4"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "JupyterHub has an Open Redirect Vulnerability"
}



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