CVE-2026-123554highCWE-407

CVE-2026-123554: high-severity vulnerability in ZcashFoundation zebra

Zebra zebrad 6.4.0 before 7.0.0 Denial of Service via Mempool Coinbase-Maturity Check

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18Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.7
Zebra zebrad 6.4.0 before 7.0.0 performs quadratic work in the mempool coinbase-maturity check because Transaction::coinbase_spend_restriction() rebuilds the transaction's output list once per spent outpoint. Any connected peer can repeatedly send unsigned transactions with many transparent inputs and outputs, which are rejected without a misbehavior score, to pin verification threads.
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
Affected products
ZcashFoundation · zebra
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