GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

GHSA-M68R-V472-JGQ9

Vulnerability from github – Published: 2026-05-05 18:10 – Updated: 2026-06-08 23:20
VLAI
Summary
JupyterHub has cross-origin form POSTs bypass XSRF (CWE-352)
Details

Summary

JupyterHub's XSRF protection (updated in 4.1.0) inappropriately treated requests with Sec-Fetch-Mode: no-cors as same-origin requests, which they are not, bypassing XSRF checks. The JSON API is not affected, only HTTP form endpoints, such as /hub/spawn and /hub/accept-share, meaning attackers could trigger server spawn (but not access the server) and if the attacker is a JupyterHub user permitted to share access to their server, cause a user to accept a share and have access to the attacker's server.

Patches

Upgrade to JupyterHub 5.4.5.

Mitigations

If a reverse proxy is in use, drop requests to JupyterHub with Sec-Fetch-Mode: no-cors.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "jupyterhub"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.1.0"
            },
            {
              "fixed": "5.4.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-40864"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-352"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-05T18:10:58Z",
    "nvd_published_at": "2026-05-22T21:16:43Z",
    "severity": "MODERATE"
  },
  "details": "## Summary\n\nJupyterHub\u0027s XSRF protection (updated in 4.1.0) inappropriately treated requests with `Sec-Fetch-Mode: no-cors` as same-origin requests, which they are not, bypassing XSRF checks. The JSON API is not affected, only HTTP form endpoints, such as `/hub/spawn` and `/hub/accept-share`, meaning attackers could trigger server spawn (but not access the server) and if the attacker is a JupyterHub user permitted to share access to their server, cause a user to accept a share and have access to the attacker\u0027s server.\n\n## Patches\n\nUpgrade to JupyterHub 5.4.5.\n\n## Mitigations\n\nIf a reverse proxy is in use, drop requests to JupyterHub with `Sec-Fetch-Mode: no-cors`.",
  "id": "GHSA-m68r-v472-jgq9",
  "modified": "2026-06-08T23:20:50Z",
  "published": "2026-05-05T18:10:58Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/jupyterhub/jupyterhub/security/advisories/GHSA-m68r-v472-jgq9"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40864"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jupyterhub/jupyterhub/commit/9c5ec277d3cda5a59de2d8c8117efa77bd941127"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/jupyterhub/jupyterhub"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "JupyterHub has cross-origin form POSTs bypass XSRF (CWE-352)"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Loading…

Detection rules are retrieved from Rulezet.

Loading…

Loading…

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.


Loading…