{"id":"CVE-2026-109366","title":"Zebra before 6.4.0 contains an improper integrity validation vulnerability in the inbound gossip download path that allows unauthenticated peers to force dropping of new blocks without penalty","summary":"Zebra before 6.4.0 contains an improper integrity validation vulnerability in the inbound gossip download path that allows unauthenticated peers to force dropping of new blocks without penalty. Attackers can serve a real block with a coi…","severity":"low","cvss":3.7,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","cwe":["CWE-354"],"published":"2026-10-12","updated":"2026-10-12","sourceUpdated":"2026-10-12T17:17:34.393","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-109366","references":[{"url":"https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-4f6v-mj46-gxg3","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/zebra-before-6.4.0-gossiped-block-drop-via-forged-coinbase-scriptsig-height","label":"disclosure@vulncheck.com"}],"tags":["nvd"],"ingestedAt":"2026-10-12T18:00:08.215Z","slug":"CVE-2026-109366","body":"## Overview\n\nZebra before 6.4.0 contains an improper integrity validation vulnerability in the inbound gossip download path that allows unauthenticated peers to force dropping of new blocks without penalty. Attackers can serve a real block with a coinbase scriptSig rewritten to height 1, which keeps the ZIP-244 block hash, triggering a behind-tip drop before consensus validation and delaying tip discovery for mining backends.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":20,"depthScoreParts":{"impact":20.4,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}