{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-107299", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-10-07T15:53:23.587Z", "datePublished": "2026-10-08T17:09:47.191Z", "dateUpdated": "2026-10-08T17:09:47.191Z"}, "containers": {"cna": {"title": "msgpack5: Reserved byte can cause unbounded stream buffering", "problemTypes": [{"descriptions": [{"cweId": "CWE-228", "lang": "en", "description": "CWE-228: Improper Handling of Syntactically Invalid Structure", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 5.9, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}}], "references": [{"name": "https://github.com/mcollina/msgpack5/security/advisories/GHSA-26wq-p25c-j6fv", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/mcollina/msgpack5/security/advisories/GHSA-26wq-p25c-j6fv"}, {"name": "https://github.com/mcollina/msgpack5/commit/85da345bf1acc18ca441741e5cf4aa0ed0d69314", "tags": ["x_refsource_MISC"], "url": "https://github.com/mcollina/msgpack5/commit/85da345bf1acc18ca441741e5cf4aa0ed0d69314"}, {"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": "2026-10-08T17:09:47.191Z"}, "descriptions": [{"lang": "en", "value": "msgpack5 is a msgpack v5 implementation for node.js and the browser. Prior to 6.1.0, the streaming decoder treats the reserved MessagePack byte 0xc1 as incomplete input instead of invalid input. When 0xc1 begins a stream, subsequent data remains buffered while the decoder waits for bytes that cannot make the value valid, allowing a remote peer to exhaust memory. This issue is fixed in version 6.1.0."}], "source": {"advisory": "GHSA-26wq-p25c-j6fv", "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, the streaming decoder treats the reserved MessagePack byte 0xc1 as incomplete input instead of invalid input. When 0xc1 begins a stream, subsequent data remains buffered while the decoder waits for bytes that cannot make the value valid, allowing a remote peer to exhaust memory. This issue is fixed in version 6.1.0."}], "id": "CVE-2026-107299", "lastModified": "2026-10-08T17:17:15.850", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 5.9, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 2.2, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-10-08T17:17:15.850", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/mcollina/msgpack5/commit/85da345bf1acc18ca441741e5cf4aa0ed0d69314"}, {"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-26wq-p25c-j6fv"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-228"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{"created": "2026-10-08T19:00:07.491613+00:00", "updated": "2026-10-08T19:00:07.491642+00:00", "vendors": []}