{"id":"CVE-2026-104423","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-104423","generatedAt":"2026-10-27T23:59:03.076Z","title":"Zebra (zebrad) before 6.2.1 contains an asymmetric resource consumption vulnerability that allows unauthenticated peers to stall block verification by pushing V6 mempool transactions with invalid Halo2 proofs.","description":"Zebra (zebrad) before 6.2.1 contains an asymmetric resource consumption vulnerability that allows unauthenticated peers to stall block verification by pushing V6 mempool transactions with invalid Halo2 proofs. Attackers can flood the shared unprioritized Halo2 verification queue with zero-fee transactions carrying zero-filled Orchard and Ironwood proofs, causing nodes to fall behind the chain tip.","published":"2026-10-02T12:17:12.000Z","lastModified":"2026-10-02T17:59:09.000Z","status":"Deferred","sourceIdentifier":"disclosure@vulncheck.com","cvss":{"version":"4.0","score":8.7,"severity":"HIGH","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-405"],"affected":[],"epss":{"score":0.00343,"percentile":0.2764,"date":"2026-10-26","history":[{"date":"2026-10-03","score":0.00343,"percentile":0.25571}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.34%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-02T12:17:12.000Z","detail":{"score":"8.7","severity":"HIGH","publishedAt":"2026-10-02T12:17:12.433Z"},"summary":"New CVE, high severity (CVSS 8.7)."}],"references":[{"url":"https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-2p4c-3q4q-p463","source":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/zebra-before-6.2.1-denial-of-service-via-uncapped-v6-shielded-proof-verification","source":"disclosure@vulncheck.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-104423","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}