{"id":"CVE-2026-109363","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-109363","summary":"ZcashFoundation Zebra 6.4.0 before 6.4.2 parses version 6 transactions carrying a pre-NU6.3 consensus branch ID, but the size computation during UnminedTx construction treats re-serialization…","details":"ZcashFoundation Zebra 6.4.0 before 6.4.2 parses version 6 transactions carrying a pre-NU6.3 consensus branch ID, but the size computation during UnminedTx construction treats re-serialization of the Orchard bundle as infallible, so the resulting error trips an expect that aborts zebrad. Unauthenticated peers can send a single pre-handshake tx message to crash the node, and can repeat this after each restart.","published":"2026-10-12T17:17:33.953","modified":"2026-10-12T17:17:33.953","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":[],"fix":{"url":"https://github.com/ZcashFoundation/zebra/commit/008abac5c99e872f283450d596d95e37851df49a","label":"ZcashFoundation/zebra@008abac"},"references":[{"type":"WEB","url":"https://github.com/ZcashFoundation/zebra/commit/008abac5c99e872f283450d596d95e37851df49a"},{"type":"WEB","url":"https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-h5rr-8pqv-grp9"},{"type":"WEB","url":"https://www.vulncheck.com/advisories/zebra-6.4.0-before-6.4.2-denial-of-service-via-malformed-v6-transaction"}],"provenance":{"sources":["OSV.dev","NVD","FIRST.org (EPSS)"],"lastVerified":"2026-10-12T17:17:33.953"}}