CVE-2026-123556

EUVD-2026-119441
ZcashFoundation Zebra from 4.5.0 before 7.0.0 contains a protection mechanism failure that bans honest peers by scoring mempool lock-time rejections at the ban threshold. Attackers can broadcast transactions locked until the current height right after each block, causing lagging nodes to ban honest relaying peers for 24 hours or until restart.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
5.3 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: 23.38%
Common Weakness Enumeration
References
https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-5h3r-fpmj-483w
https://www.vulncheck.com/advisories/zebra-4.5.0-before-7.0.0-honest-peer-ban-via-mempool-lock-time-scoring