Vulnerability-Lookup

Vulnerability from bitnami_vulndb

Published

2026-09-21 09:07

Modified

2026-09-21 09:26

Summary

tarfile extraction filters allow file modification and content disclosure via hard link to symlink

Details

In CPython 3.13 and earlier, the tarfile module's data and tar extraction filters are vulnerable to crafted archives containing a hard link to a symbolic link. Such archives may cause extraction to modify the permissions or modification time of a file outside the destination directory, or expose the contents of that file within the extracted tree.

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "python",
        "purl": "pkg:bitnami/python"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.14.0"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/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",
          "type": "CVSS_V4"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-82049"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:python:python:*:*:*:*:*:*:*:*"
    ],
    "severity": "High"
  },
  "details": "In CPython 3.13 and earlier, the tarfile\u00a0module\u0027s data\u00a0and tar extraction filters are vulnerable to crafted archives containing a hard link to a symbolic link. Such archives may cause extraction to modify the permissions or modification time of a file outside the destination directory, or expose the contents of that file within the extracted tree.",
  "id": "BIT-python-2026-82049",
  "modified": "2026-09-21T09:26:48.669Z",
  "published": "2026-09-21T09:07:26.646Z",
  "references": [
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2026/09/14/27"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/5a57248b22ad3b9aafcaaadae2c304a1923daeca"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/b38be2e6cf9d989075ab73412c63e003ebad4ff3"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/b8f23e307097552eaea2604383a12ab280520d0d"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/issues/157190"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/pull/157191"
    },
    {
      "type": "WEB",
      "url": "https://mail.python.org/archives/list/security-announce@python.org/thread/EFJWGAZJA56AKSBR2WHMHQZO7RRLZPRH/"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-82049"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "tarfile extraction filters allow file modification and content disclosure via hard link to symlink"
}

CVE-2026-82049 (GCVE-0-2026-82049)

Vulnerability from cvelistv5 – Published: 2026-09-14 19:14 – Updated: 2026-09-16 03:56

Title

tarfile extraction filters allow file modification and content disclosure via hard link to symlink

Summary

Severity

8.4 (High)


                        
                          CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/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 2026-09-15 00:00 UTC

CWE

CWE-59

Assigner

PSF mitre root

References

7 references

URL	Tags
https://github.com/python/cpython/commit/5a57248b…	patch
https://github.com/python/cpython/issues/157190	issue-tracking
https://github.com/python/cpython/pull/157191	patch
https://mail.python.org/archives/list/security-an…	vendor-advisory
https://github.com/python/cpython/commit/b38be2e6…	patch
https://github.com/python/cpython/commit/b8f23e30…	patch
http://www.openwall.com/lists/oss-security/2026/0…

Impacted products

1 product

Vendor	Product	Version
Python Software Foundation	CPython	Affected: 0 , < 3.14.0b1 (python)

Credits

Jing Qian (https://github.com/Civitasmass) Stan Ulbrych (https://github.com/StanFromIreland) Petr Viktorin (https://github.com/encukou)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-82049",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-15T00:00:00+00:00",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-16T03:56:12.084Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2026-09-14T20:07:50.158Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/09/14/27"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "modules": [
            "tarfile"
          ],
          "product": "CPython",
          "repo": "https://github.com/python/cpython",
          "vendor": "Python Software Foundation",
          "versions": [
            {
              "lessThan": "3.14.0b1",
              "status": "affected",
              "version": "0",
              "versionType": "python"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "Jing Qian (https://github.com/Civitasmass)"
        },
        {
          "lang": "en",
          "type": "coordinator",
          "value": "Stan Ulbrych (https://github.com/StanFromIreland)"
        },
        {
          "lang": "en",
          "type": "remediation reviewer",
          "value": "Petr Viktorin (https://github.com/encukou)"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "type": "text/html",
              "value": "In CPython 3.13 and earlier, the \u003cspan\u003etarfile\u003c/span\u003e\u0026nbsp;module\u0027s \u003cspan\u003edata\u003c/span\u003e\u0026nbsp;and \u003cspan\u003etar\u003c/span\u003e extraction filters are vulnerable to crafted archives containing a hard link to a symbolic link. Such archives may cause extraction to modify the permissions or modification time of a file outside the destination directory, or expose the contents of that file within the extracted tree."
            }
          ],
          "value": "In CPython 3.13 and earlier, the tarfile\u00a0module\u0027s data\u00a0and tar extraction filters are vulnerable to crafted archives containing a hard link to a symbolic link. Such archives may cause extraction to modify the permissions or modification time of a file outside the destination directory, or expose the contents of that file within the extracted tree."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "LOCAL",
            "baseScore": 8.4,
            "baseSeverity": "HIGH",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "PASSIVE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-59",
              "description": "CWE-59",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-15T00:34:01.076Z",
        "orgId": "28c92f92-d60d-412d-b760-e73465c3df22",
        "shortName": "PSF"
      },
      "references": [
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/commit/5a57248b22ad3b9aafcaaadae2c304a1923daeca"
        },
        {
          "tags": [
            "issue-tracking"
          ],
          "url": "https://github.com/python/cpython/issues/157190"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/pull/157191"
        },
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://mail.python.org/archives/list/security-announce@python.org/thread/EFJWGAZJA56AKSBR2WHMHQZO7RRLZPRH/"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/commit/b38be2e6cf9d989075ab73412c63e003ebad4ff3"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/commit/b8f23e307097552eaea2604383a12ab280520d0d"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "tarfile extraction filters allow file modification and content disclosure via hard link to symlink",
      "x_generator": {
        "engine": "cvelib 1.8.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "28c92f92-d60d-412d-b760-e73465c3df22",
    "assignerShortName": "PSF",
    "cveId": "CVE-2026-82049",
    "datePublished": "2026-09-14T19:14:03.873Z",
    "dateReserved": "2026-08-27T22:23:05.514Z",
    "dateUpdated": "2026-09-16T03:56:12.084Z",
    "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.

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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.

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Vulnerability from bitnami_vulndb

CVE-2026-82049 (GCVE-0-2026-82049)

Tags

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