{"id":"CVE-2026-107300","aliases":["GHSA-5x5g-h9x8-2fh9"],"url":"https://o3.security/vulnerability/CVE-2026-107300","summary":"msgpack5: Many buffered values can exhaust the streaming decoder stack","details":"### Impact\n\nThe streaming decoder recursively invokes itself for every complete value remaining in a chunk. A single chunk containing many small valid MessagePack values can exhaust the JavaScript call stack and interrupt the process or stream.\n\n### Patches\n\nThe streaming decoder now drains concatenated values iteratively with constant call-stack depth.\n\n### Workarounds\n\nLimit the number of MessagePack values accepted in one chunk, or split large batches before passing them to the decoder stream.","published":"2026-10-08T17:11:13.552Z","modified":"2026-10-21T02:54:36.446209438Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"npm","name":"msgpack5","fixedVersion":"6.1.0"}],"fix":{"url":"https://github.com/mcollina/msgpack5/commit/77fbef144d05def5d16fc22c37caa64c0a7efeba","label":"mcollina/msgpack5@77fbef1"},"references":[{"type":"WEB","url":"https://github.com/mcollina/msgpack5/releases/tag/v6.1.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/107xxx/CVE-2026-107300.json"},{"type":"ADVISORY","url":"https://github.com/mcollina/msgpack5/security/advisories/GHSA-5x5g-h9x8-2fh9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-107300"},{"type":"FIX","url":"https://github.com/mcollina/msgpack5/commit/77fbef144d05def5d16fc22c37caa64c0a7efeba"},{"type":"PACKAGE","url":"https://github.com/mcollina/msgpack5"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-21T02:54:36.446209438Z"}}