Vulnerability-Lookup

CVE-2026-40934 (GCVE-0-2026-40934)

Vulnerability from cvelistv5 – Published: 2026-05-05 21:31 – Updated: 2026-05-07 12:48

Title

jupyter-server authentication cookies remain valid after password reset due to static cookie secret

Summary

Jupyter Server is the backend for Jupyter web applications. In versions 2.17.0 and earlier, the secret used to sign authentication cookies is persisted to a static file at ~/.local/share/jupyter/runtime/jupyter_cookie_secret and is never rotated when a user changes their password. After a password reset and server restart, any previously issued authentication cookie remains cryptographically valid because the signing key has not changed. An attacker who has captured a session cookie through any means retains full authenticated access to the server regardless of subsequent password changes. This affects deployments using password-based authentication, particularly shared or public-facing servers where credential rotation is expected to revoke existing sessions. This issue has been fixed in version 2.18.0.

Severity

7.6 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-05-07 03:55 UTC

CWE

CWE-613 - Insufficient Session Expiration

Assigner

GitHub_M mitre root

References

1 reference

URL	Tags
https://github.com/jupyter-server/jupyter_server/…	x_refsource_CONFIRM

Impacted products

1 product

Vendor	Product	Version	CPE status
jupyter-server	jupyter_server	Affected: < 2.18.0	guessed

Show details on NVD website

JSON

To clipboard

{
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    "adp": [
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        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-40934",
                "options": [
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                  },
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                    "Technical Impact": "total"
                  }
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                "timestamp": "2026-05-07T03:55:46.015938Z",
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        }
      ],
      "metrics": [
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            "attackComplexity": "LOW",
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            "baseSeverity": "HIGH",
            "privilegesRequired": "LOW",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
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            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          }
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        }
      ],
      "source": {
        "advisory": "GHSA-5mrq-x3x5-8v8f",
        "discovery": "UNKNOWN"
      },
      "title": "jupyter-server authentication cookies remain valid after password reset due to static cookie secret"
    }
  },
  "cveMetadata": {
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    "redhat_vex": {
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      "title": "jupyter-server: Jupyter Server: Authentication bypass due to unrotated cookie secret",
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    "vulnrichment": {
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}

cleanstart-2026-gg76429

Vulnerability from cleanstart

Published

2026-07-30 07:10

Modified

2026-09-04 12:17

Summary

Security fixes in tensorflow-gpu-jupyter 2.21.0-r5

Details

Package tensorflow-gpu-jupyter version 2.21.0-r5 fixes 28 vulnerabilities: ghsa-rch3-82jr-f9w9, ghsa-mqcg-5x36-vfcg, ghsa-37w4-hwhx-4rc4, ghsa-mf9v-mfxr-j63j, ghsa-5mrq-x3x5-8v8f...

References

URL

Type

https://tensorflow.org

WEB

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "CleanStart",
        "name": "tensorflow-gpu-jupyter"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.21.0-r5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.21.0-r5"
      ]
    }
  ],
  "credits": [],
  "database_specific": {},
  "details": "Package tensorflow-gpu-jupyter version 2.21.0-r5 fixes 28 vulnerabilities: ghsa-rch3-82jr-f9w9, ghsa-mqcg-5x36-vfcg, ghsa-37w4-hwhx-4rc4, ghsa-mf9v-mfxr-j63j, ghsa-5mrq-x3x5-8v8f...",
  "id": "CLEANSTART-2026-GG76429",
  "modified": "2026-09-04T12:17:57Z",
  "published": "2026-07-30T07:10:53Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://tensorflow.org"
    }
  ],
  "related": [],
  "schema_version": "1.7.3",
  "summary": "Security fixes in tensorflow-gpu-jupyter 2.21.0-r5",
  "upstream": [
    "ghsa-rch3-82jr-f9w9",
    "ghsa-mqcg-5x36-vfcg",
    "ghsa-37w4-hwhx-4rc4",
    "ghsa-mf9v-mfxr-j63j",
    "ghsa-5mrq-x3x5-8v8f",
    "ghsa-5789-5fc7-67v3",
    "ghsa-qccp-gfcp-xxvc",
    "ghsa-24qx-w28j-9m6p",
    "ghsa-8mp2-v27r-99xp",
    "ghsa-qh7q-6qm3-653w",
    "ghsa-65pc-fj4g-8rjx",
    "ghsa-6269-cqxg-mhhv",
    "ghsa-ccfx-mfmx-2fx9",
    "ghsa-v87v-83h2-53w7",
    "CVE-2026-45409",
    "CVE-2026-35397",
    "CVE-2026-40110",
    "CVE-2026-40934",
    "CVE-2025-61669",
    "CVE-2026-40171",
    "CVE-2026-42266",
    "CVE-2026-42557",
    "CVE-2026-33079",
    "CVE-2026-44897",
    "CVE-2026-44898",
    "CVE-2026-44899",
    "CVE-2026-44431",
    "CVE-2026-44432"
  ]
}

FKIE_CVE-2026-40934

Vulnerability from fkie_nvd - Published: 2026-05-05 22:16 - Updated: 2026-07-25 11:10

Severity

6.8 (Medium) - CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

Summary

References

	URL	Tags
	security-advisories@github.com	https://github.com/jupyter-server/jupyter_server/security/advisories/GHSA-5mrq-x3x5-8v8f	Exploit, Mitigation, Vendor Advisory

Impacted products

	Vendor	Product	Version
	jupyter	jupyter_server	*

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "jupyter_server",
          "vendor": "jupyter-server",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 2.18.0"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:jupyter:jupyter_server:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "E0B6C703-7E28-4F23-9878-E157975C32A4",
              "versionEndExcluding": "2.18.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Jupyter Server is the backend for Jupyter web applications. In versions 2.17.0 and earlier, the secret used to sign authentication cookies is persisted to a static file at ~/.local/share/jupyter/runtime/jupyter_cookie_secret and is never rotated when a user changes their password. After a password reset and server restart, any previously issued authentication cookie remains cryptographically valid because the signing key has not changed. An attacker who has captured a session cookie through any means retains full authenticated access to the server regardless of subsequent password changes. This affects deployments using password-based authentication, particularly shared or public-facing servers where credential rotation is expected to revoke existing sessions. This issue has been fixed in version 2.18.0."
    },
    {
      "lang": "es",
      "value": "Jupyter Server es el backend para las aplicaciones web de Jupyter. En las versiones 2.17.0 y anteriores, el secreto utilizado para firmar las cookies de autenticaci\u00f3n se persiste en un archivo est\u00e1tico en ~/.local/share/jupyter/runtime/jupyter_cookie_secret y nunca se rota cuando un usuario cambia su contrase\u00f1a. Despu\u00e9s de un restablecimiento de contrase\u00f1a y un reinicio del servidor, cualquier cookie de autenticaci\u00f3n emitida previamente permanece criptogr\u00e1ficamente v\u00e1lida porque la clave de firma no ha cambiado. Un atacante que ha capturado una cookie de sesi\u00f3n por cualquier medio retiene acceso autenticado completo al servidor independientemente de los cambios de contrase\u00f1a posteriores. Esto afecta a las implementaciones que utilizan autenticaci\u00f3n basada en contrase\u00f1a, particularmente servidores compartidos o de cara al p\u00fablico donde se espera que la rotaci\u00f3n de credenciales revoque las sesiones existentes. Este problema ha sido solucionado en la versi\u00f3n 2.18.0."
    }
  ],
  "id": "CVE-2026-40934",
  "lastModified": "2026-07-25T11:10:00.100",
  "metrics": {
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      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.8,
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          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
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        "impactScore": 5.2,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 7.6,
          "baseSeverity": "HIGH",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "LOW",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/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",
          "version": "4.0",
          "vulnAvailabilityImpact": "NONE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-40934",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-05-07T03:55:46.015938Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-05-05T22:16:00.820",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Mitigation",
        "Vendor Advisory"
      ],
      "url": "https://github.com/jupyter-server/jupyter_server/security/advisories/GHSA-5mrq-x3x5-8v8f"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-613"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}

GHSA-5MRQ-X3X5-8V8F

Vulnerability from github – Published: 2026-05-05 17:03 – Updated: 2026-06-06 00:27

Summary

Jupyter Server's Authentication Cookies Remain Valid After Password Reset and Server Restart

Details

Summary

A persistent cookie secret vulnerability allows authenticated users to maintain indefinite access even after password changes.

The cookie secret used to sign authentication cookies is stored in a permanent file (~/.local/share/jupyter/runtime/jupyter_cookie_secret) that is never automatically rotated or cleared, allowing stolen or compromised cookies to remain valid indefinitely regardless of password resets.

PoC

Start a Jupyter server with password authentication: jupyter server password, jupyter server
Log in with the password and capture the authentication cookie (e.g., just login with a browser).
Change the password to revoke access: jupyter server password
Restart the server
Use the old stolen cookie => remains valid and provides full authenticated access.

Impact

All jupyter-server deployments using password authentication where security incidents may occur
Multi-user systems where one user's compromised session should be revocable by administrators
Shared or public-facing Jupyter servers where credential rotation is a security requirement
Any deployment where password changes are expected to revoke existing sessions

Patches

Jupyter Server 2.18+

Workaround

rm ~/.local/share/jupyter/runtime/jupyter_cookie_secret
# Then restart the server

Severity

6.8 (Medium)


                  
                    CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

7.6 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 2.17.0"
      },
      "package": {
        "ecosystem": "PyPI",
        "name": "jupyter-server"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.18.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-40934"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-613"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-05T17:03:24Z",
    "nvd_published_at": "2026-05-05T22:16:00Z",
    "severity": "HIGH"
  },
  "details": "## Summary\n\nA persistent cookie secret vulnerability allows authenticated users to maintain indefinite access even after password changes. \n\nThe cookie secret used to sign authentication cookies is stored in a permanent file (`~/.local/share/jupyter/runtime/jupyter_cookie_secret`) that is never automatically rotated or cleared, allowing stolen or compromised cookies to remain valid indefinitely regardless of password resets.\n\n## PoC\n\n- Start a Jupyter server with password authentication: `jupyter server password`, `jupyter server`\n- Log in with the password and capture the authentication cookie (e.g., just login with a browser).\n- Change the password to revoke access: `jupyter server password`\n- Restart the server\n- Use the old stolen cookie =\u003e remains valid and provides full authenticated access.\n\n## Impact\n\n- All jupyter-server deployments using password authentication where security incidents may occur\n- Multi-user systems where one user\u0027s compromised session should be revocable by administrators\n- Shared or public-facing Jupyter servers where credential rotation is a security requirement\n- Any deployment where password changes are expected to revoke existing sessions\n\n## Patches\n\nJupyter Server 2.18+\n\n## Workaround\n\n```bash\nrm ~/.local/share/jupyter/runtime/jupyter_cookie_secret\n# Then restart the server\n```",
  "id": "GHSA-5mrq-x3x5-8v8f",
  "modified": "2026-06-06T00:27:08Z",
  "published": "2026-05-05T17:03:24Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/jupyter-server/jupyter_server/security/advisories/GHSA-5mrq-x3x5-8v8f"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40934"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/jupyter-server/jupyter_server"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/jupyter-server/PYSEC-2026-69.yaml"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Jupyter Server\u0027s Authentication Cookies Remain Valid After Password Reset and Server Restart"
}

OPENSUSE-SU-2026:10710-1

Vulnerability from csaf_opensuse - Published: 2026-05-06 00:00 - Updated: 2026-05-06 00:00

Summary

python311-jupyter-server-2.18.1-1.1 on GA media

Severity

Moderate

Scope

4 vulnerabilities in this advisory, including CVE-2026-40934.

CVE-2026-40934

Recommended: 24 products

Open the full advisory

PYSEC-2026-69

Vulnerability from pysec - Published: 2026-05-05 22:16 - Updated: 2026-05-20 09:19

Details

Severity

6.8 (Medium)


                  
                    CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

Impacted products

Name	purl
jupyter-server	pkg:pypi/jupyter-server

Aliases

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "jupyter-server",
        "purl": "pkg:pypi/jupyter-server"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.18.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.0.0",
        "0.0.1",
        "0.0.2",
        "0.0.3",
        "0.0.4",
        "0.0.5",
        "0.1.0",
        "0.1.1",
        "0.2.0",
        "0.2.1",
        "0.3.0",
        "1.0.0",
        "1.0.0rc0",
        "1.0.0rc1",
        "1.0.0rc10",
        "1.0.0rc11",
        "1.0.0rc12",
        "1.0.0rc13",
        "1.0.0rc14",
        "1.0.0rc15",
        "1.0.0rc16",
        "1.0.0rc2",
        "1.0.0rc3",
        "1.0.0rc4",
        "1.0.0rc5",
        "1.0.0rc6",
        "1.0.0rc7",
        "1.0.0rc8",
        "1.0.0rc9",
        "1.0.1",
        "1.0.10",
        "1.0.11",
        "1.0.2",
        "1.0.3",
        "1.0.4",
        "1.0.5",
        "1.0.6",
        "1.0.7",
        "1.0.8",
        "1.0.9",
        "1.1.0",
        "1.1.1",
        "1.1.2",
        "1.1.3",
        "1.1.4",
        "1.10.0",
        "1.10.1",
        "1.10.2",
        "1.11.0",
        "1.11.1",
        "1.11.2",
        "1.12.0",
        "1.12.1",
        "1.13.0",
        "1.13.1",
        "1.13.2",
        "1.13.3",
        "1.13.4",
        "1.13.5",
        "1.15.0",
        "1.15.1",
        "1.15.2",
        "1.15.3",
        "1.15.4",
        "1.15.5",
        "1.15.6",
        "1.16.0",
        "1.17.0",
        "1.17.1",
        "1.18.0",
        "1.18.1",
        "1.19.0",
        "1.19.1",
        "1.2.0",
        "1.2.1",
        "1.2.2",
        "1.2.3",
        "1.21.0",
        "1.23.0",
        "1.23.1",
        "1.23.2",
        "1.23.3",
        "1.23.4",
        "1.23.5",
        "1.23.6",
        "1.24.0",
        "1.3.0",
        "1.4.0",
        "1.4.1",
        "1.5.0",
        "1.5.1",
        "1.6.0",
        "1.6.1",
        "1.6.2",
        "1.6.3",
        "1.6.4",
        "1.7.0",
        "1.7.0a1",
        "1.7.0a2",
        "1.8.0",
        "1.9.0",
        "2.0.0",
        "2.0.0a0",
        "2.0.0a1",
        "2.0.0a2",
        "2.0.0b0",
        "2.0.0b1",
        "2.0.0rc0",
        "2.0.0rc1",
        "2.0.0rc2",
        "2.0.0rc3",
        "2.0.0rc4",
        "2.0.0rc5",
        "2.0.0rc6",
        "2.0.0rc7",
        "2.0.0rc8",
        "2.0.1",
        "2.0.2",
        "2.0.3",
        "2.0.4",
        "2.0.5",
        "2.0.6",
        "2.0.7",
        "2.1.0",
        "2.10.0",
        "2.10.1",
        "2.11.0",
        "2.11.1",
        "2.11.2",
        "2.12.0",
        "2.12.1",
        "2.12.2",
        "2.12.3",
        "2.12.4",
        "2.12.5",
        "2.13.0",
        "2.14.0",
        "2.14.1",
        "2.14.2",
        "2.15.0",
        "2.16.0",
        "2.17.0",
        "2.2.0",
        "2.2.1",
        "2.3.0",
        "2.4.0",
        "2.5.0",
        "2.6.0",
        "2.7.0",
        "2.7.1",
        "2.7.2",
        "2.7.3",
        "2.8.0",
        "2.9.0",
        "2.9.1"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-40934",
    "GHSA-5mrq-x3x5-8v8f"
  ],
  "details": "Jupyter Server is the backend for Jupyter web applications. In versions 2.17.0 and earlier, the secret used to sign authentication cookies is persisted to a static file at ~/.local/share/jupyter/runtime/jupyter_cookie_secret and is never rotated when a user changes their password. After a password reset and server restart, any previously issued authentication cookie remains cryptographically valid because the signing key has not changed. An attacker who has captured a session cookie through any means retains full authenticated access to the server regardless of subsequent password changes. This affects deployments using password-based authentication, particularly shared or public-facing servers where credential rotation is expected to revoke existing sessions. This issue has been fixed in version 2.18.0.",
  "id": "PYSEC-2026-69",
  "modified": "2026-05-20T09:19:02.981614Z",
  "published": "2026-05-05T22:16:00.820Z",
  "references": [
    {
      "type": "EVIDENCE",
      "url": "https://github.com/jupyter-server/jupyter_server/security/advisories/GHSA-5mrq-x3x5-8v8f"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

ubuntu-cve-2026-40934

Vulnerability from osv_ubuntu

Published

2026-05-05 22:16

Modified

2026-05-20 15:27

Summary

Details

Severity

7.6 (High)


                    
                      CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

6.8 (Medium)


                    
                      CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-40934	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-40934	REPORT
	https://github.com/jupyter-server/jupyter_server/…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "jupyter-server",
            "binary_version": "1.13.1-1"
          },
          {
            "binary_name": "python3-jupyter-server",
            "binary_version": "1.13.1-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "jupyter-server",
        "purl": "pkg:deb/ubuntu/jupyter-server@1.13.1-1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.2.2-1",
        "1.13.1-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "jupyter-server",
            "binary_version": "1.23.3-2"
          },
          {
            "binary_name": "python3-jupyter-server",
            "binary_version": "1.23.3-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "jupyter-server",
        "purl": "pkg:deb/ubuntu/jupyter-server@1.23.3-2?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.23.3-1",
        "1.23.3-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "jupyter-server",
            "binary_version": "2.15.0-1"
          },
          {
            "binary_name": "python3-jupyter-server",
            "binary_version": "2.15.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "jupyter-server",
        "purl": "pkg:deb/ubuntu/jupyter-server@2.15.0-1?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.14.2-5",
        "2.15.0-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "jupyter-server",
            "binary_version": "2.17.0-1"
          },
          {
            "binary_name": "python3-jupyter-server",
            "binary_version": "2.17.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "jupyter-server",
        "purl": "pkg:deb/ubuntu/jupyter-server@2.17.0-1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.15.0-1",
        "2.17.0-1"
      ]
    }
  ],
  "aliases": [],
  "details": "Jupyter Server is the backend for Jupyter web applications. In versions 2.17.0 and earlier, the secret used to sign authentication cookies is persisted to a static file at ~/.local/share/jupyter/runtime/jupyter_cookie_secret and is never rotated when a user changes their password. After a password reset and server restart, any previously issued authentication cookie remains cryptographically valid because the signing key has not changed. An attacker who has captured a session cookie through any means retains full authenticated access to the server regardless of subsequent password changes. This affects deployments using password-based authentication, particularly shared or public-facing servers where credential rotation is expected to revoke existing sessions. This issue has been fixed in version 2.18.0.",
  "id": "UBUNTU-CVE-2026-40934",
  "modified": "2026-05-20T15:27:26Z",
  "published": "2026-05-05T22:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-40934"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-40934"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/jupyter-server/jupyter_server/security/advisories/GHSA-5mrq-x3x5-8v8f"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-40934"
  ]
}

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.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

CVE-2026-40934 (GCVE-0-2026-40934)

cleanstart-2026-gg76429

Vulnerability from cleanstart

FKIE_CVE-2026-40934

GHSA-5MRQ-X3X5-8V8F

Summary

PoC

Impact

Patches

Workaround

OPENSUSE-SU-2026:10710-1

PYSEC-2026-69

ubuntu-cve-2026-40934

Vulnerability from osv_ubuntu

Tags

Sightings

Nomenclature