CVE-2026-16052

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-16052", "assignerOrgId": "28c92f92-d60d-412d-b760-e73465c3df22", "state": "PUBLISHED", "assignerShortName": "PSF", "dateReserved": "2026-07-17T10:34:29.475Z", "datePublished": "2026-11-12T16:28:03.251Z", "dateUpdated": "2026-11-12T16:28:03.251Z"}, "containers": {"cna": {"affected": [{"defaultStatus": "unaffected", "modules": ["http", "http.cookies"], "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": "Qi Deng (https://github.com/ikow)"}, {"lang": "en", "type": "coordinator", "value": "Stan Ulbrych (https://github.com/StanFromIreland)"}, {"lang": "en", "type": "remediation developer", "value": "Brett Smith (https://github.com/brettcs)"}, {"lang": "en", "type": "remediation reviewer", "value": "Seth Larson (https://github.com/sethmlarson)"}, {"lang": "en", "type": "remediation reviewer", "value": "Victor Stinner (https://github.com/vstinner)"}, {"lang": "en", "type": "remediation reviewer", "value": "Senthil Kumaran (https://github.com/orsenthil)"}], "descriptions": [{"lang": "en", "supportingMedia": [{"type": "text/html", "value": "The http.cookies.Morsel class allows separator semicolons in attribute\nvalues\nand includes them verbatim in all output formats. An attacker who can\ncontrol\nthese values could use this to relax the cookie's Domain or SameSite\nrestrictions."}], "value": "The http.cookies.Morsel class allows separator semicolons in attribute\nvalues\nand includes them verbatim in all output formats. An attacker who can\ncontrol\nthese values could use this to relax the cookie's Domain or SameSite\nrestrictions."}], "metrics": [{"cvssV4_0": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "attackVector": "NETWORK", "baseScore": 2.3, "baseSeverity": "LOW", "exploitMaturity": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "PASSIVE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "LOW", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "problemTypes": [{"descriptions": [{"cweId": "CWE-74", "description": "CWE-74", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"orgId": "28c92f92-d60d-412d-b760-e73465c3df22", "shortName": "PSF", "dateUpdated": "2026-11-12T16:28:03.251Z"}, "references": [{"url": "https://github.com/python/cpython/pull/161711"}, {"url": "https://github.com/python/cpython/issues/161707"}, {"url": "https://mail.python.org/archives/list/security-announce@python.org/thread/IZL4QUFV7PKGT2JYSU2DCBMLTWYJDGKZ/"}], "source": {"discovery": "UNKNOWN"}, "title": "Cookie Attribute Injection via Unescaped Semicolons in http.cookies.Morsel"}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "modules": ["http", "http.cookies"], "product": "CPython", "repo": "https://github.com/python/cpython", "vendor": "Python Software Foundation", "versions": [{"lessThan": "3.16.0", "status": "affected", "version": "0", "versionType": "python"}]}], "source": "cna@python.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "The http.cookies.Morsel class allows separator semicolons in attribute\nvalues\nand includes them verbatim in all output formats. An attacker who can\ncontrol\nthese values could use this to relax the cookie's Domain or SameSite\nrestrictions."}], "id": "CVE-2026-16052", "lastModified": "2026-11-12T17:17:44.353", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 2.3, "baseSeverity": "LOW", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "PASSIVE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/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", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "LOW", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "cna@python.org", "type": "Secondary"}]}, "published": "2026-11-12T17:17:44.237", "references": [{"source": "cna@python.org", "url": "https://github.com/python/cpython/issues/161707"}, {"source": "cna@python.org", "url": "https://github.com/python/cpython/pull/161711"}, {"source": "cna@python.org", "url": "https://mail.python.org/archives/list/security-announce@python.org/thread/IZL4QUFV7PKGT2JYSU2DCBMLTWYJDGKZ/"}], "sourceIdentifier": "cna@python.org", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-74"}], "source": "cna@python.org", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,3.16.0)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "CPython", "source": "cna", "vendor": "Python Software Foundation"}, "product": "cpython", "vendor": "python"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,3.16.0)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "CPython", "source": "cna", "vendor": "Python Software Foundation"}, "product": "cpython", "vendor": "python_software_foundation"}], "created": "2026-11-13T04:15:14.471563+00:00", "updated": "2026-11-13T04:15:14.471611+00:00", "vendors": ["python", "python$PRODUCT$cpython", "python_software_foundation", "python_software_foundation$PRODUCT$cpython"]}