{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-109366", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-10-12T14:21:32.595Z", "datePublished": "2026-10-12T16:05:43.620Z", "dateUpdated": "2026-10-12T16:05:43.620Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-10-12T16:05:43.620Z"}, "datePublic": "2026-09-28T00:00:00.000Z", "title": "Zebra before 6.4.0 Gossiped Block Drop via Forged Coinbase scriptSig Height", "descriptions": [{"lang": "en", "value": "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 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."}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "Improper Validation of Integrity Check Value", "cweId": "CWE-354", "type": "CWE"}]}], "affected": [{"vendor": "ZcashFoundation", "product": "zebra", "defaultStatus": "unaffected", "packageURL": "pkg:cargo/zebrad", "versions": [{"version": "0", "status": "affected", "versionType": "semver", "lessThan": "6.4.0"}, {"version": "6.4.0", "status": "unaffected", "versionType": "semver"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:zfnd:zebra:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.4.0"}]}]}], "metrics": [{"format": "CVSS", "cvssV4_0": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "LOW", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 6.3, "baseSeverity": "MEDIUM"}}, {"format": "CVSS", "cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L", "attackVector": "NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "LOW", "baseScore": 3.7, "baseSeverity": "LOW"}}], "references": [{"url": "https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-4f6v-mj46-gxg3", "tags": ["vendor-advisory"], "name": "GitHub Security Advisory (GHSA-4f6v-mj46-gxg3)"}, {"name": "VulnCheck Advisory: Zebra before 6.4.0 Gossiped Block Drop via Forged Coinbase scriptSig Height", "tags": ["third-party-advisory"], "url": "https://www.vulncheck.com/advisories/zebra-before-6.4.0-gossiped-block-drop-via-forged-coinbase-scriptsig-height"}], "credits": [{"lang": "en", "value": "craftsoldier", "type": "reporter"}, {"lang": "en", "value": "arya2", "type": "finder"}, {"lang": "en", "value": "conradoplg", "type": "finder"}, {"lang": "en", "value": "mpguerra", "type": "coordinator"}], "x_generator": {"engine": "vulncheck-endgame"}}}}

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