Vulnerability-Lookup

ubuntu-cve-2026-39377

Vulnerability from osv_ubuntu

Published

2026-04-21 01:16

Modified

2026-05-20 15:27

Summary

Details

The nbconvert tool, jupyter nbconvert, converts Jupyter notebooks to various other formats via Jinja templates. Versions 6.5 through 7.17.0 allow arbitrary file writes to locations outside the intended output directory when processing notebooks containing crafted cell attachment filenames. The ExtractAttachmentsPreprocessor passes attachment filenames directly to the filesystem without sanitization, enabling path traversal attacks. This vulnerability provides complete control over both the destination path and file extension. Version 7.17.1 contains a patch.

Severity

6.5 (Medium)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-39377	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-39377	REPORT
	https://github.com/jupyter/nbconvert/security/adv…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "jupyter-nbconvert",
            "binary_version": "5.3.1-1"
          },
          {
            "binary_name": "python-nbconvert",
            "binary_version": "5.3.1-1"
          },
          {
            "binary_name": "python3-nbconvert",
            "binary_version": "5.3.1-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "nbconvert",
        "purl": "pkg:deb/ubuntu/nbconvert@5.3.1-1?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.2.0-4",
        "5.3.1-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "jupyter-nbconvert",
            "binary_version": "5.6.1-1"
          },
          {
            "binary_name": "python3-nbconvert",
            "binary_version": "5.6.1-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "nbconvert",
        "purl": "pkg:deb/ubuntu/nbconvert@5.6.1-1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "5.4-2ubuntu2",
        "5.6.0-1",
        "5.6.0-2",
        "5.6.1-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "jupyter-nbconvert",
            "binary_version": "6.4.0-1"
          },
          {
            "binary_name": "python3-nbconvert",
            "binary_version": "6.4.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "nbconvert",
        "purl": "pkg:deb/ubuntu/nbconvert@6.4.0-1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "5.6.1-3",
        "6.1.0-1",
        "6.3.0-1",
        "6.4.0-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "jupyter-nbconvert",
            "binary_version": "6.5.3-5"
          },
          {
            "binary_name": "python3-nbconvert",
            "binary_version": "6.5.3-5"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "nbconvert",
        "purl": "pkg:deb/ubuntu/nbconvert@6.5.3-5?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "6.5.3-4",
        "6.5.3-5"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "jupyter-nbconvert",
            "binary_version": "7.16.6-1"
          },
          {
            "binary_name": "python3-nbconvert",
            "binary_version": "7.16.6-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "nbconvert",
        "purl": "pkg:deb/ubuntu/nbconvert@7.16.6-1?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "7.16.6-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "jupyter-nbconvert",
            "binary_version": "7.17.0-1"
          },
          {
            "binary_name": "python3-nbconvert",
            "binary_version": "7.17.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "nbconvert",
        "purl": "pkg:deb/ubuntu/nbconvert@7.17.0-1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "7.16.6-1",
        "7.17.0-1"
      ]
    }
  ],
  "aliases": [],
  "details": "The nbconvert tool, jupyter nbconvert, converts Jupyter notebooks to various other formats via Jinja templates. Versions 6.5 through 7.17.0 allow arbitrary file writes to locations outside the intended output directory when processing notebooks containing crafted cell attachment filenames. The `ExtractAttachmentsPreprocessor` passes attachment filenames directly to the filesystem without sanitization, enabling path traversal attacks. This vulnerability provides complete control over both the destination path and file extension. Version 7.17.1 contains a patch.",
  "id": "UBUNTU-CVE-2026-39377",
  "modified": "2026-05-20T15:27:25Z",
  "published": "2026-04-21T01:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-39377"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-39377"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/jupyter/nbconvert/security/advisories/GHSA-4c99-qj7h-p3vg"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-39377"
  ]
}

CVE-2026-39377 (GCVE-0-2026-39377)

Vulnerability from cvelistv5 – Published: 2026-04-21 00:14 – Updated: 2026-04-21 19:49

Title

nbconvert has an Arbitrary File Write via Path Traversal in Cell Attachment Filenames

Summary

The nbconvert tool, jupyter nbconvert, converts Jupyter notebooks to various other formats via Jinja templates. Versions 6.5 through 7.17.0 allow arbitrary file writes to locations outside the intended output directory when processing notebooks containing crafted cell attachment filenames. The `ExtractAttachmentsPreprocessor` passes attachment filenames directly to the filesystem without sanitization, enabling path traversal attacks. This vulnerability provides complete control over both the destination path and file extension. Version 7.17.1 contains a patch.

Severity

6.5 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-21 16:01 UTC

CWE

CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CWE-73 - External Control of File Name or Path

Assigner

GitHub_M mitre root

References

2 references

URL	Tags
https://github.com/jupyter/nbconvert/security/adv…	x_refsource_CONFIRM
https://github.com/jupyter/nbconvert/releases/tag…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
jupyter	nbconvert	Affected: >= 6.5, < 7.17.1

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-39377",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-21T16:01:22.179013Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-21T19:49:24.475Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "nbconvert",
          "vendor": "jupyter",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 6.5, \u003c 7.17.1"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The nbconvert tool, jupyter nbconvert, converts Jupyter notebooks to various other formats via Jinja templates. Versions 6.5 through 7.17.0 allow arbitrary file writes to locations outside the intended output directory when processing notebooks containing crafted cell attachment filenames. The `ExtractAttachmentsPreprocessor` passes attachment filenames directly to the filesystem without sanitization, enabling path traversal attacks. This vulnerability provides complete control over both the destination path and file extension. Version 7.17.1 contains a patch."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-22",
              "description": "CWE-22: Improper Limitation of a Pathname to a Restricted Directory (\u0027Path Traversal\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-73",
              "description": "CWE-73: External Control of File Name or Path",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-21T00:14:59.937Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/jupyter/nbconvert/security/advisories/GHSA-4c99-qj7h-p3vg",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/jupyter/nbconvert/security/advisories/GHSA-4c99-qj7h-p3vg"
        },
        {
          "name": "https://github.com/jupyter/nbconvert/releases/tag/v7.17.1",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/jupyter/nbconvert/releases/tag/v7.17.1"
        }
      ],
      "source": {
        "advisory": "GHSA-4c99-qj7h-p3vg",
        "discovery": "UNKNOWN"
      },
      "title": "nbconvert has an Arbitrary File Write via Path Traversal in Cell Attachment Filenames"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-39377",
    "datePublished": "2026-04-21T00:14:59.937Z",
    "dateReserved": "2026-04-06T21:29:17.350Z",
    "dateUpdated": "2026-04-21T19:49:24.475Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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.