{"id":"GHSA-8f34-f56x-9xph","summary":"msgpack5: Truncated map32 headers throw an unexpected error","details":"### Impact\n\nA truncated `map32` header causes an out-of-bounds buffer read and throws `RangeError` instead of `IncompleteBufferError`. Applications that rely on `IncompleteBufferError` to wait for additional bytes may terminate a request, stream, or worker unexpectedly. No adjacent memory is disclosed because the buffer implementation checks bounds.\n\n### Patches\n\nThe decoder now validates the complete five-byte `map32` header before reading its length and reports truncated input as `IncompleteBufferError`.\n\n### Workarounds\n\nRequire at least five bytes before decoding a value beginning with `0xdf`, or catch `RangeError` and treat it as incomplete input only for truncated `map32` headers.","aliases":["CVE-2026-107302"],"modified":"2026-10-08T18:00:09.698423726Z","published":"2026-10-08T17:40:10Z","database_specific":{"cwe_ids":["CWE-125"],"severity":"HIGH","github_reviewed":true,"github_reviewed_at":"2026-10-08T17:40:10Z","nvd_published_at":null},"references":[{"type":"WEB","url":"https://github.com/mcollina/msgpack5/security/advisories/GHSA-8f34-f56x-9xph"},{"type":"WEB","url":"https://github.com/mcollina/msgpack5/commit/15443a1f2aa682a6aa37f1705ac628de5b866ad1"},{"type":"PACKAGE","url":"https://github.com/mcollina/msgpack5"},{"type":"WEB","url":"https://github.com/mcollina/msgpack5/releases/tag/v6.1.0"}],"affected":[{"package":{"name":"msgpack5","ecosystem":"npm","purl":"pkg:npm/msgpack5"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"6.1.0"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-8f34-f56x-9xph/GHSA-8f34-f56x-9xph.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}