CVE-2026-107301

{"id": "CVE-2026-107301", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-107301", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-10-14T01:02:40.915617Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:L", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "LOW", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 4.2, "exploitabilityScore": 2.2}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "mcollina", "product": "msgpack5", "versions": [{"status": "affected", "version": "< 6.1.0"}]}]}], "published": "2026-10-08T17:17:16.143", "references": [{"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", "source": "security-advisories@github.com"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-1321"}]}], "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."}], "lastModified": "2026-10-14T01:17:05.583", "sourceIdentifier": "security-advisories@github.com"}