{"id":"CVE-2026-44499","summary":"ZEBRA: Permanent Block Discovery Halt via Gossip Queue Saturation and Syncer Poisoning","details":"ZEBRA is a Zcash node written entirely in Rust. Prior to version 4.4.0, a composite denial-of-service vulnerability in Zebra's block discovery pipeline allows an unauthenticated remote attacker to permanently halt all new block discovery on a targeted node. The attack exploits three independent weaknesses in the gossip, syncer, and download subsystems — all exercisable from a single TCP connection — to create a monotonically growing block deficit that never self-heals. This issue has been patched in version 4.4.0.","aliases":["GHSA-h9hm-m2xj-4rq9"],"modified":"2026-07-15T01:49:16.103490020Z","published":"2026-05-08T15:11:24.837Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44499.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-770"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44499.json"},{"type":"ADVISORY","url":"https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-h9hm-m2xj-4rq9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-44499"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/zcashfoundation/zebra","events":[{"introduced":"0"},{"fixed":"589d64b9b7ea6ab4c32ecab41ba6b74f26907940"}],"database_specific":{"source":"AFFECTED_FIELD","extracted_events":[{"introduced":"0"},{"fixed":"4.4.0"}]}}],"versions":["v4.3.1","4.3.1","v4.3.0","v4.2.0","v4.1.0","v4.0.0","v3.1.0","v3.0.0","v3.0.0-rc.0","v2.5.0","v2.0.1","v2.4.2","v2.3.0","v2.4.0","v2.0.0","v2.2.0","v2.1.0","v2.0.0-rc.0","v1.9.0","v1.8.0","v1.7.0","v1.6.1","v1.6.0","v1.5.2","v1.5.1","v1.5.0","v1.4.0","v1.3.0","v1.2.0","v1.1.0","v1.0.1","v1.0.0","v1.0.0-rc.9","v1.0.0-rc.8","v1.0.0-rc.7","v1.0.0-rc.6","v1.0.0-rc.5","v1.0.0-rc.0","v1.0.0-rc.4","v1.0.0-rc.3","v1.0.0-rc.2","v1.0.0-rc.1","v1.0.0-beta.15","v1.0.0-beta.14","v1.0.0-beta.13","v1.0.0-beta.12","v1.0.0-beta.11","v1.0.0-beta.10","v1.0.0-beta.9","v1.0.0-beta.8","v1.0.0-beta.7","v1.0.0-beta.6","v1.0.0-beta.5","v1.0.0-beta.4","v1.0.0-beta.3","v1.0.0-beta.2","v1.0.0-beta.1","v1.0.0-beta.0","v1.0.0-alpha.19","v1.0.0-alpha.18","v1.0.0-alpha.17","v1.0.0-alpha.16","v1.0.0-alpha.15","v1.0.0-alpha.14","v1.0.0-alpha.13","v1.0.0-alpha.12","v1.0.0-alpha.11","v1.0.0-alpha.10","v1.0.0-alpha.9","v1.0.0-alpha.8","v1.0.0-alpha.7","v1.0.0-alpha.6","v1.0.0-alpha.5","v1.0.0-alpha.4","v1.0.0-alpha.3","v1.0.0-alpha.2","v1.0.0-alpha.1","v1.0.0-alpha.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-44499.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"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"}]}