{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-107301", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-10-07T15:53:23.587Z", "datePublished": "2026-10-08T17:13:00.613Z", "dateUpdated": "2026-10-08T17:13:00.613Z"}, "containers": {"cna": {"title": "msgpack5: Partial options disable prototype protection", "problemTypes": [{"descriptions": [{"cweId": "CWE-1321", "lang": "en", "description": "CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 6.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:L", "version": "3.1"}}], "references": [{"name": "https://github.com/mcollina/msgpack5/security/advisories/GHSA-8hq7-ggx2-cc6m", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/mcollina/msgpack5/security/advisories/GHSA-8hq7-ggx2-cc6m"}, {"name": "https://github.com/mcollina/msgpack5/commit/20e82600ac9462e679c8a45e5723315f21e2c774", "tags": ["x_refsource_MISC"], "url": "https://github.com/mcollina/msgpack5/commit/20e82600ac9462e679c8a45e5723315f21e2c774"}, {"name": "https://github.com/mcollina/msgpack5/releases/tag/v6.1.0", "tags": ["x_refsource_MISC"], "url": "https://github.com/mcollina/msgpack5/releases/tag/v6.1.0"}], "affected": [{"vendor": "mcollina", "product": "msgpack5", "versions": [{"version": "< 6.1.0", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-10-08T17:13:00.613Z"}, "descriptions": [{"lang": "en", "value": "msgpack5 is a msgpack v5 implementation for node.js and the browser. Prior to 6.1.0, constructing msgpack5 with an empty or partial options object disables the default protoAction: 'error' protection. A decoded map containing a __proto__ key can then replace the decoded object's prototype, potentially changing inherited properties or downstream behavior, although Object.prototype is not modified globally. This issue is fixed in version 6.1.0."}], "source": {"advisory": "GHSA-8hq7-ggx2-cc6m", "discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"product": "msgpack5", "vendor": "mcollina", "versions": [{"status": "affected", "version": "< 6.1.0"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "msgpack5 is a msgpack v5 implementation for node.js and the browser. Prior to 6.1.0, constructing msgpack5 with an empty or partial options object disables the default protoAction: 'error' protection. A decoded map containing a __proto__ key can then replace the decoded object's prototype, potentially changing inherited properties or downstream behavior, although Object.prototype is not modified globally. This issue is fixed in version 6.1.0."}], "id": "CVE-2026-107301", "lastModified": "2026-10-08T20:48:36.970", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 6.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:L", "version": "3.1"}, "exploitabilityScore": 2.2, "impactScore": 4.2, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-10-08T17:17:16.143", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/mcollina/msgpack5/commit/20e82600ac9462e679c8a45e5723315f21e2c774"}, {"source": "security-advisories@github.com", "url": "https://github.com/mcollina/msgpack5/releases/tag/v6.1.0"}, {"source": "security-advisories@github.com", "url": "https://github.com/mcollina/msgpack5/security/advisories/GHSA-8hq7-ggx2-cc6m"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-1321"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{"created": "2026-10-08T19:00:07.491281+00:00", "updated": "2026-10-08T19:00:07.491287+00:00", "vendors": []}