{"id":"CVE-2026-123554","title":"Zebra zebrad 6.4.0 before 7.0.0 Denial of Service via Mempool Coinbase-Maturity Check","summary":"Zebra zebrad 6.4.0 before 7.0.0 performs quadratic work in the mempool coinbase-maturity check because Transaction::coinbase_spend_restriction() rebuilds the transaction's output list once per spent outpoint. Any connected peer can repea…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cvssSource":"cna","cwe":["CWE-407"],"vendor":"ZcashFoundation","product":"zebra","affected":["zebra >= 6.4.0 < 7.0.0"],"published":"2026-11-08","updated":"2026-11-08","sourceUpdated":"2026-11-08T01:37:56.894Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-123554","references":[{"url":"https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-7jp4-mq53-4cvq","label":"GitHub Security Advisory (GHSA-7jp4-mq53-4cvq)"},{"url":"https://github.com/ZcashFoundation/zebra/commit/08743d669b33a19bce2a5d54001bd468c03a196e","label":"Patch Commit"},{"url":"https://www.vulncheck.com/advisories/zebra-zebrad-6.4.0-before-7.0.0-denial-of-service-via-mempool-coinbase-maturity-check","label":"VulnCheck Advisory: Zebra zebrad 6.4.0 before 7.0.0 Denial of Service via Mempool Coinbase-Maturity Check"}],"tags":["cve.org"],"ingestedAt":"2026-11-08T02:43:18.668Z","slug":"CVE-2026-123554","body":"## Overview\n\nZebra zebrad 6.4.0 before 7.0.0 performs quadratic work in the mempool coinbase-maturity check because Transaction::coinbase_spend_restriction() rebuilds the transaction's output list once per spent outpoint. Any connected peer can repeatedly send unsigned transactions with many transparent inputs and outputs, which are rejected without a misbehavior score, to pin verification threads.\n\n## Affected\n\n- `zebra >= 6.4.0 < 7.0.0`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}