CVE-2026-11940
tarfile.extractall() with the 'data' or 'tar' filter could be bypassed by a crafted archive where a hardlink references a symlink stored at a deeper name than the hardlink itself. The extraction fallback validated the symlink at it's archived location but recreated it at the hardlink's shallower path, letting a relative target the filter judged contained escape the destination directory. This allowed a malicious tar archive to create a symlink pointing outside the destination, enabling out-of-destination file reads or writes. This was an incomplete fix of CVE-2025-4330.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/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
- Puntuación base: 7.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.75%
- Percentil entre todas las CVEs puntuadas: 53
- Fecha de la puntuación: 1/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-22, CWE-59
Referencias
- https://github.com/python/cpython/commit/0f852b3f07dd8e71e40326a51c02afbf16a42cc5
- https://github.com/python/cpython/commit/27dd970bf6b17ebca7c8ed486a40ab043ed7af8f
- https://github.com/python/cpython/commit/672825e2f36a57e173959b0d9d409d4560dab8df
- https://github.com/python/cpython/commit/771d12dda5140313db0ac550292987975651bbde
- https://github.com/python/cpython/commit/79c06bd5c6afa3c440d50faf7ee1b147c8832b4c
- https://github.com/python/cpython/commit/be13e86f6b9788a6f4d0419dffef72cbae5865c9
- https://github.com/python/cpython/commit/e5fdbd8d5aa923bd9111b112ea73bd6ec7c47877
- https://github.com/python/cpython/issues/151558
- https://github.com/python/cpython/pull/151559
- https://mail.python.org/archives/list/security-announce@python.org/thread/LD6QIISNQFQYOIEPJNEUIPV7S3V76FZH/
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-11940",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-11940",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-06-23T17:57:25.652265Z"
}
}
],
"cvssMetricV40": [
{
"type": "Secondary",
"source": "cna@python.org",
"cvssData": {
"Safety": "NOT_DEFINED",
"version": "4.0",
"Recovery": "NOT_DEFINED",
"baseScore": 7.8,
"Automatable": "NOT_DEFINED",
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/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",
"exploitMaturity": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"privilegesRequired": "NONE",
"subIntegrityImpact": "HIGH",
"vulnIntegrityImpact": "NONE",
"integrityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"vulnAvailabilityImpact": "NONE",
"availabilityRequirement": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"subConfidentialityImpact": "HIGH",
"vulnConfidentialityImpact": "NONE",
"confidentialityRequirement": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED"
}
}
]
},
"affected": [
{
"source": "cna@python.org",
"affectedData": [
{
"repo": "https://github.com/python/cpython",
"vendor": "Python Software Foundation",
"product": "CPython",
"versions": [
{
"status": "affected",
"version": "0",
"lessThan": "3.10.21",
"versionType": "python"
},
{
"status": "affected",
"version": "3.11.0",
"lessThan": "3.11.16",
"versionType": "python"
},
{
"status": "affected",
"version": "3.12.0",
"lessThan": "3.12.14",
"versionType": "python"
},
{
"status": "affected",
"version": "3.13.0",
"lessThan": "3.13.15",
"versionType": "python"
},
{
"status": "affected",
"version": "3.14.0",
"lessThan": "3.14.7",
"versionType": "python"
},
{
"status": "affected",
"version": "3.15.0a1",
"lessThan": "3.15.0b4",
"versionType": "python"
}
],
"defaultStatus": "unaffected"
}
]
}
],
"published": "2026-06-23T17:16:40.847",
"references": [
{
"url": "https://github.com/python/cpython/commit/0f852b3f07dd8e71e40326a51c02afbf16a42cc5",
"source": "cna@python.org"
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{
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"source": "cna@python.org"
},
{
"url": "https://github.com/python/cpython/commit/672825e2f36a57e173959b0d9d409d4560dab8df",
"source": "cna@python.org"
},
{
"url": "https://github.com/python/cpython/commit/771d12dda5140313db0ac550292987975651bbde",
"source": "cna@python.org"
},
{
"url": "https://github.com/python/cpython/commit/79c06bd5c6afa3c440d50faf7ee1b147c8832b4c",
"source": "cna@python.org"
},
{
"url": "https://github.com/python/cpython/commit/be13e86f6b9788a6f4d0419dffef72cbae5865c9",
"source": "cna@python.org"
},
{
"url": "https://github.com/python/cpython/commit/e5fdbd8d5aa923bd9111b112ea73bd6ec7c47877",
"source": "cna@python.org"
},
{
"url": "https://github.com/python/cpython/issues/151558",
"source": "cna@python.org"
},
{
"url": "https://github.com/python/cpython/pull/151559",
"source": "cna@python.org"
},
{
"url": "https://mail.python.org/archives/list/security-announce@python.org/thread/LD6QIISNQFQYOIEPJNEUIPV7S3V76FZH/",
"source": "cna@python.org"
}
],
"vulnStatus": "Awaiting Analysis",
"weaknesses": [
{
"type": "Secondary",
"source": "cna@python.org",
"description": [
{
"lang": "en",
"value": "CWE-22"
},
{
"lang": "en",
"value": "CWE-59"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "tarfile.extractall() with the 'data' or 'tar'\n filter could be bypassed by a crafted archive where a hardlink \nreferences a symlink stored at a deeper name than the hardlink itself. \nThe extraction fallback validated the symlink at it's archived location \nbut recreated it at the hardlink's shallower\npath, letting a relative\n target the filter judged contained escape the destination directory. \nThis allowed a malicious tar archive to create a symlink pointing \noutside the destination, enabling out-of-destination file reads or \nwrites. This was an incomplete fix of CVE-2025-4330."
}
],
"lastModified": "2026-08-13T01:16:51.627",
"sourceIdentifier": "cna@python.org"
}