CVE-2026-123554

CVSS 8.7 (high) · published 2026-11-08

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.

Weakness: CWE-407

Source: NVD CVE-2026-123554

References

• https://github.com/ZcashFoundation/zebra/commit/08743d669b33a19bce2a5d54001bd468c03a196e
• https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-7jp4-mq53-4cvq
• https://www.vulncheck.com/advisories/zebra-zebrad-6.4.0-before-7.0.0-denial-of-service-via-mempool-coinbase-maturity-check

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