{"id":"CVE-2026-107299","sourceIdentifier":"security-advisories@github.com","published":"2026-10-08T17:17:15.850","lastModified":"2026-10-09T16:17:22.147","vulnStatus":"Deferred","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."}],"affected":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"mcollina","product":"msgpack5","versions":[{"version":"< 6.1.0","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":5.9,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":2.2,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-10-08T20:23:17.872522Z","id":"CVE-2026-107299","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Secondary","description":[{"lang":"en","value":"CWE-228"}]}],"references":[{"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","source":"security-advisories@github.com"}]}