{"id":"CVE-2026-107299","revision":"56c7de8813e6477e87544f6e65753428","records":[{"revision":"56c7de8813e6477e87544f6e65753428","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-107299","aliases":[],"title":"msgpack5: Reserved byte can cause unbounded stream buffering","description":"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.","state":0,"publishedAt":"2026-10-08T17:09:47.191+00:00","modifiedAt":"2026-10-09T15:15:00.98+00:00","affected":[{"ecosystem":"Vendor product","name":"msgpack5","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"mcollina\",\n                    \"product\": \"msgpack5\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 6.1.0\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","score":5.9,"severity":"MEDIUM"}],"references":["https://github.com/mcollina/msgpack5/security/advisories/GHSA-26wq-p25c-j6fv","https://github.com/mcollina/msgpack5/commit/85da345bf1acc18ca441741e5cf4aa0ed0d69314","https://github.com/mcollina/msgpack5/releases/tag/v6.1.0"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-107299","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-107299","identifiers":["CVE-2026-107299"]},"retained":false,"historicalAffected":[]}],"coverage":[]}