CVE-2026-123556: medium-severity vulnerability in ZcashFoundation zebra
Zebra 4.5.0 before 7.0.0 Honest Peer Ban via Mempool Lock-Time Scoring
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.9epss 0.3%
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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Affected products
ZcashFoundation · zebraRelated CVEs — ZcashFoundation zebra
In the same product, most dangerous first.
CVE-2026-34202CRITICALZebra node crash — V5 transaction hash panic (P2P reachable)EPSS 0.8%CVE-2026-52736HIGHZEBRA: Block suppression via NU5 same-header body poisoning of sent-hash cacheEPSS 0.6%CVE-2026-52829HIGHZEBRA: IPv4-Mapped Mempool Misbehavior Update Aborts Zebra Address BookEPSS 0.6%CVE-2026-52731MEDIUMZEBRA: Full node denial of service via non-ASCII LongPollId in getblocktemplateEPSS 0.5%CVE-2026-52739MEDIUMZEBRA: Repeated Non-Finalized Shielded Transaction Aborts Zebra Before Duplicate-Nullifier RejectionEPSS 0.5%CVE-2026-52732MEDIUMZEBRA: Mempool transaction admission denial via single-peer inbound queue saturationEPSS 0.5%