CVE-2026-19672 (GCVE-0-2026-19672)

Vulnerability from cvelistv5 – Published: 2026-08-19 15:24 – Updated: 2026-08-19 15:24
VLAI
Title
tarfile extraction filter bypass allows creation of directories outside the destination
Summary
The tarfile module's tar and data extraction filters created directories outside the destination for members whose name leaves the destination and returns to it, such as ../evil/../dest/sub/file. The containment check used the resolved path, but intermediate directories were created from the name as given. Only empty directories are created outside the destination. Member contents are still extracted inside it. To return to the destination the member's name must contain the destination directory's own final component, so extraction into a secure randomised directory is not affected. This affects POSIX platforms only. On Windows, .. components are collapsed before the path reaches the filesystem, so the directories outside the destination are never created.
Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N
Assigner
References
Impacted products
Vendor Product Version CPE status
Python Software Foundation CPython Affected: 0 , < 3.16.0 (python)
guessed Create a notification for this product.
Credits
Lohinth (https://github.com/l0h1nth) Stan Ulbrych (https://github.com/StanFromIreland) Petr Viktorin (https://github.com/encukou) Ethan Furman (https://github.com/ethanfurman)
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "modules": [
            "tarfile"
          ],
          "product": "CPython",
          "repo": "https://github.com/python/cpython",
          "vendor": "Python Software Foundation",
          "versions": [
            {
              "lessThan": "3.16.0",
              "status": "affected",
              "version": "0",
              "versionType": "python"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "Lohinth (https://github.com/l0h1nth)"
        },
        {
          "lang": "en",
          "type": "coordinator",
          "value": "Stan Ulbrych (https://github.com/StanFromIreland)"
        },
        {
          "lang": "en",
          "type": "remediation reviewer",
          "value": "Petr Viktorin (https://github.com/encukou)"
        },
        {
          "lang": "en",
          "type": "remediation reviewer",
          "value": "Ethan Furman (https://github.com/ethanfurman)"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "type": "text/html",
              "value": "The \u003cspan\u003etarfile\u003c/span\u003e module\u0027s \u003cspan\u003etar\u003c/span\u003e and \u003cspan\u003edata\u003c/span\u003e\n extraction filters created directories outside the destination for \nmembers whose name leaves the destination and returns to it, such as \u003cspan\u003e../evil/../dest/sub/file\u003c/span\u003e. The containment check used the resolved path, but intermediate directories were created from the name as given.\u003cbr\u003e\u003cbr\u003eOnly\n empty directories are created outside the destination. Member contents \nare still extracted inside it. To return to the destination the member\u0027s\n name must contain the destination directory\u0027s own final component, so \nextraction into a secure randomised directory is not affected.\u003cbr\u003e\u003cbr\u003eThis affects POSIX platforms only. On Windows, \u003cspan\u003e..\u003c/span\u003e components are collapsed before the path reaches the filesystem, so the directories outside the destination are never created."
            }
          ],
          "value": "The tarfile module\u0027s tar and data\n extraction filters created directories outside the destination for \nmembers whose name leaves the destination and returns to it, such as ../evil/../dest/sub/file. The containment check used the resolved path, but intermediate directories were created from the name as given.\n\nOnly\n empty directories are created outside the destination. Member contents \nare still extracted inside it. To return to the destination the member\u0027s\n name must contain the destination directory\u0027s own final component, so \nextraction into a secure randomised directory is not affected.\n\nThis affects POSIX platforms only. On Windows, .. components are collapsed before the path reaches the filesystem, so the directories outside the destination are never created."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 6.3,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "LOW",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-19T15:24:08.616Z",
        "orgId": "28c92f92-d60d-412d-b760-e73465c3df22",
        "shortName": "PSF"
      },
      "references": [
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/python/cpython/pull/156000"
        },
        {
          "tags": [
            "issue-tracking"
          ],
          "url": "https://github.com/python/cpython/pull/156000"
        },
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://mail.python.org/archives/list/security-announce@python.org/thread/J2WT2ALRWEXQJOB3C7Q2HYWUXP3CINWO/"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "tarfile extraction filter bypass allows creation of directories outside the destination"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "28c92f92-d60d-412d-b760-e73465c3df22",
    "assignerShortName": "PSF",
    "cveId": "CVE-2026-19672",
    "datePublished": "2026-08-19T15:24:08.616Z",
    "dateReserved": "2026-08-12T21:17:15.148Z",
    "dateUpdated": "2026-08-19T15:24:08.616Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-19672",
      "date": "2026-08-22",
      "epss": "0.00324",
      "percentile": "0.25398"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-19672\",\"sourceIdentifier\":\"cna@python.org\",\"published\":\"2026-08-19T16:17:06.593\",\"lastModified\":\"2026-08-19T16:17:06.593\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"The tarfile module\u0027s tar and data\\n extraction filters created directories outside the destination for \\nmembers whose name leaves the destination and returns to it, such as ../evil/../dest/sub/file. The containment check used the resolved path, but intermediate directories were created from the name as given.\\n\\nOnly\\n empty directories are created outside the destination. Member contents \\nare still extracted inside it. To return to the destination the member\u0027s\\n name must contain the destination directory\u0027s own final component, so \\nextraction into a secure randomised directory is not affected.\\n\\nThis affects POSIX platforms only. On Windows, .. components are collapsed before the path reaches the filesystem, so the directories outside the destination are never created.\"}],\"affected\":[{\"source\":\"cna@python.org\",\"affectedData\":[{\"vendor\":\"Python Software Foundation\",\"product\":\"CPython\",\"defaultStatus\":\"unaffected\",\"modules\":[\"tarfile\"],\"repo\":\"https://github.com/python/cpython\",\"versions\":[{\"version\":\"0\",\"lessThan\":\"3.16.0\",\"versionType\":\"python\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"cna@python.org\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/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\",\"baseScore\":6.3,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"PRESENT\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"NONE\",\"vulnIntegrityImpact\":\"NONE\",\"vulnAvailabilityImpact\":\"NONE\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"LOW\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}]},\"references\":[{\"url\":\"https://github.com/python/cpython/pull/156000\",\"source\":\"cna@python.org\"},{\"url\":\"https://github.com/python/cpython/pull/156000\",\"source\":\"cna@python.org\"},{\"url\":\"https://mail.python.org/archives/list/security-announce@python.org/thread/J2WT2ALRWEXQJOB3C7Q2HYWUXP3CINWO/\",\"source\":\"cna@python.org\"}]}}"
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





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.


Detection rules are retrieved from Rulezet.