{"id":"CVE-2026-104424","state":"PUBLISHED","title":"Zebra before 6.1.0 Incorrect Block Size Calculation in getblocktemplate","description":"Zebra before 6.1.0 contains an incorrect calculation vulnerability in its ZIP-317 block template selector that omits header and transaction-count size from the block budget. Attackers can place valid selectable transactions in a victim miner's mempool to shape templates into oversized blocks, causing rejection and wasted proof-of-work.","publishedAt":"2026-10-02T11:38:05.827Z","updatedAt":"2026-10-06T02:38:24.183Z","severity":{"score":6.3,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["ZcashFoundation zebra"],"affected":[{"vendor":"ZcashFoundation","product":"zebra","packageURL":"pkg:cargo/zebrad","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"6.1.0","versionType":"semver"},{"version":"6.1.0","status":"unaffected","versionType":"semver"}]}],"references":["https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-95m2-vx53-v2jw","https://www.vulncheck.com/advisories/zebra-before-6.1.0-incorrect-block-size-calculation-in-getblocktemplate"],"weaknesses":["CWE-131"],"ingestedAt":"2026-10-29T20:10:23.711Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/104xxx/CVE-2026-104424.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-104424","state":"PUBLISHED","datePublished":"2026-10-02T11:38:05.827Z","dateUpdated":"2026-10-06T02:38:24.183Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-10-02T00:46:23.830Z"},"containers":{"cna":{"title":"Zebra before 6.1.0 Incorrect Block Size Calculation in getblocktemplate","descriptions":[{"lang":"en","value":"Zebra before 6.1.0 contains an incorrect calculation vulnerability in its ZIP-317 block template selector that omits header and transaction-count size from the block budget. Attackers can place valid selectable transactions in a victim miner's mempool to shape templates into oversized blocks, causing rejection and wasted proof-of-work."}],"affected":[{"vendor":"ZcashFoundation","product":"zebra","packageURL":"pkg:cargo/zebrad","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"6.1.0","versionType":"semver"},{"version":"6.1.0","status":"unaffected","versionType":"semver"}]}],"references":[{"url":"https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-95m2-vx53-v2jw","tags":["vendor-advisory"],"name":"GitHub Security Advisory (GHSA-95m2-vx53-v2jw)"},{"url":"https://www.vulncheck.com/advisories/zebra-before-6.1.0-incorrect-block-size-calculation-in-getblocktemplate","name":"VulnCheck Advisory: Zebra before 6.1.0 Incorrect Block Size Calculation in getblocktemplate","tags":["third-party-advisory"]}],"metrics":[{"format":"CVSS","cvssV4_0":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","attackVector":"NETWORK","attackComplexity":"HIGH","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"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-131","lang":"en","description":"Incorrect Calculation of Buffer Size","type":"CWE"}]}],"providerMetadata":{"shortName":"VulnCheck","orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateUpdated":"2026-10-02T11:38:05.827Z"},"datePublic":"2026-07-17T00:00:00.000Z","cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:zfnd:zebra:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.0"}]}]}],"credits":[{"lang":"en","value":"ebfull","type":"reporter"},{"lang":"en","value":"upbqdn","type":"finder"}],"x_generator":{"engine":"vulncheck-endgame"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-06T02:38:13.781191Z","id":"CVE-2026-104424","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-06T02:38:24.183Z"}}]}}}