{"api_version":"1","generated_at":"2026-06-30T18:51:56+00:00","cve":"CVE-2026-11940","urls":{"html":"https://cve.report/CVE-2026-11940","api":"https://cve.report/api/cve/CVE-2026-11940.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-11940","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-11940"},"summary":{"title":"tarfile extraction filter bypass allows escaping the destination directory","description":"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.","state":"PUBLISHED","assigner":"PSF","published_at":"2026-06-23 17:16:40","updated_at":"2026-06-30 16:16:35"},"problem_types":["CWE-22","CWE-59","CWE-22 CWE-22","CWE-59 CWE-59"],"metrics":[{"version":"4.0","source":"cna@python.org","type":"Secondary","score":"7.8","severity":"HIGH","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","data":{"version":"4.0","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","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"HIGH","subIntegrityImpact":"HIGH","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"}},{"version":"4.0","source":"CNA","type":"CVSS","score":"7.8","severity":"HIGH","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","data":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"NONE","attackVector":"NETWORK","baseScore":7.8,"baseSeverity":"HIGH","exploitMaturity":"NOT_DEFINED","privilegesRequired":"NONE","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"HIGH","subIntegrityImpact":"HIGH","userInteraction":"NONE","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","version":"4.0","vulnAvailabilityImpact":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnerabilityResponseEffort":"NOT_DEFINED"}}],"references":[{"url":"https://github.com/python/cpython/issues/151558","name":"https://github.com/python/cpython/issues/151558","refsource":"cna@python.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/python/cpython/commit/672825e2f36a57e173959b0d9d409d4560dab8df","name":"https://github.com/python/cpython/commit/672825e2f36a57e173959b0d9d409d4560dab8df","refsource":"cna@python.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/python/cpython/commit/79c06bd5c6afa3c440d50faf7ee1b147c8832b4c","name":"https://github.com/python/cpython/commit/79c06bd5c6afa3c440d50faf7ee1b147c8832b4c","refsource":"cna@python.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/python/cpython/commit/27dd970bf6b17ebca7c8ed486a40ab043ed7af8f","name":"https://github.com/python/cpython/commit/27dd970bf6b17ebca7c8ed486a40ab043ed7af8f","refsource":"cna@python.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/python/cpython/pull/151559","name":"https://github.com/python/cpython/pull/151559","refsource":"cna@python.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/python/cpython/commit/be13e86f6b9788a6f4d0419dffef72cbae5865c9","name":"https://github.com/python/cpython/commit/be13e86f6b9788a6f4d0419dffef72cbae5865c9","refsource":"cna@python.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/python/cpython/commit/771d12dda5140313db0ac550292987975651bbde","name":"https://github.com/python/cpython/commit/771d12dda5140313db0ac550292987975651bbde","refsource":"cna@python.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://mail.python.org/archives/list/security-announce@python.org/thread/LD6QIISNQFQYOIEPJNEUIPV7S3V76FZH/","name":"https://mail.python.org/archives/list/security-announce@python.org/thread/LD6QIISNQFQYOIEPJNEUIPV7S3V76FZH/","refsource":"cna@python.org","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-11940","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-11940","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Python Software Foundation","product":"CPython","version":"affected 3.15.0 python","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[{"source":"CNA","value":"Haruki Oyama (https://github.com/harukioya)","lang":"en"},{"source":"CNA","value":"Stan Ulbrych (https://github.com/StanFromIreland)","lang":"en"},{"source":"CNA","value":"Petr Viktorin (https://github.com/encukou)","lang":"en"}],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"11940","cve":"CVE-2026-11940","epss":"0.005990000","percentile":"0.442010000","score_date":"2026-06-28","updated_at":"2026-06-29 00:14:19"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"metrics":[{"other":{"content":{"id":"CVE-2026-11940","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","timestamp":"2026-06-23T17:57:25.652265Z","version":"2.0.3"},"type":"ssvc"}}],"providerMetadata":{"dateUpdated":"2026-06-23T17:57:32.525Z","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP"},"title":"CISA ADP Vulnrichment"}],"cna":{"affected":[{"defaultStatus":"unaffected","product":"CPython","repo":"https://github.com/python/cpython","vendor":"Python Software Foundation","versions":[{"lessThan":"3.15.0","status":"affected","version":"0","versionType":"python"}]}],"credits":[{"lang":"en","type":"reporter","value":"Haruki Oyama (https://github.com/harukioya)"},{"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":"<span>tarfile.extractall()</span> with the <span>'data'</span> or <span>'tar'</span>\n filter could be bypassed by a crafted archive where a hardlink \nreferences a symlink stored at a deeper name than the hardlink itself.&nbsp; \nThe extraction fallback validated the symlink at it's archived location \nbut recreated it at the hardlink's shallower<br>path, letting a relative\n target the filter judged contained escape the destination directory.&nbsp; \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."}],"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."}],"metrics":[{"cvssV4_0":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"NONE","attackVector":"NETWORK","baseScore":7.8,"baseSeverity":"HIGH","exploitMaturity":"NOT_DEFINED","privilegesRequired":"NONE","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"HIGH","subIntegrityImpact":"HIGH","userInteraction":"NONE","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","version":"4.0","vulnAvailabilityImpact":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnerabilityResponseEffort":"NOT_DEFINED"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-22","description":"CWE-22","lang":"en","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-59","description":"CWE-59","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-06-30T15:13:33.568Z","orgId":"28c92f92-d60d-412d-b760-e73465c3df22","shortName":"PSF"},"references":[{"tags":["patch"],"url":"https://github.com/python/cpython/pull/151559"},{"tags":["vendor-advisory"],"url":"https://mail.python.org/archives/list/security-announce@python.org/thread/LD6QIISNQFQYOIEPJNEUIPV7S3V76FZH/"},{"tags":["issue-tracking"],"url":"https://github.com/python/cpython/issues/151558"},{"tags":["patch"],"url":"https://github.com/python/cpython/commit/27dd970bf6b17ebca7c8ed486a40ab043ed7af8f"},{"tags":["patch"],"url":"https://github.com/python/cpython/commit/672825e2f36a57e173959b0d9d409d4560dab8df"},{"tags":["patch"],"url":"https://github.com/python/cpython/commit/771d12dda5140313db0ac550292987975651bbde"},{"tags":["patch"],"url":"https://github.com/python/cpython/commit/79c06bd5c6afa3c440d50faf7ee1b147c8832b4c"},{"tags":["patch"],"url":"https://github.com/python/cpython/commit/be13e86f6b9788a6f4d0419dffef72cbae5865c9"}],"source":{"discovery":"UNKNOWN"},"title":"tarfile extraction filter bypass allows escaping the destination directory","x_generator":{"engine":"cvelib 1.8.0"}}},"cveMetadata":{"assignerOrgId":"28c92f92-d60d-412d-b760-e73465c3df22","assignerShortName":"PSF","cveId":"CVE-2026-11940","datePublished":"2026-06-23T16:04:17.321Z","dateReserved":"2026-06-10T19:50:59.923Z","dateUpdated":"2026-06-30T15:13:33.568Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-06-23 17:16:40","lastModifiedDate":"2026-06-30 16:16:35","problem_types":["CWE-22","CWE-59","CWE-22 CWE-22","CWE-59 CWE-59"],"metrics":{"cvssMetricV40":[{"source":"cna@python.org","type":"Secondary","cvssData":{"version":"4.0","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","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"HIGH","subIntegrityImpact":"HIGH","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"}}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-06-23T17:57:25.652265Z","id":"CVE-2026-11940","options":[{"exploitation":"none"},{"automatable":"yes"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"11940","Ordinal":"1","Title":"tarfile extraction filter bypass allows escaping the destination","CVE":"CVE-2026-11940","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"11940","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"tarfile extraction filter bypass allows escaping the destination"}]}}}