Vulnerability in Zcashfoundation Zebra
CVE-2026-123559
Zebra before 7.0.0 contains an inefficient algorithmic complexity vulnerability that allows unauthenticated peers to exhaust verification threads by submitting transactions with many transparent inputs. Attackers can relay invalid transactions with tens of thousands of inputs, forcing quadratic ZIP-244 or ZIP-243 digest recomputation that stalls Rayon-backed block verification for minutes.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- GitHub Security Advisory (GHSA-j4cw-58mj-7w6v) (vendor-advisory)
- VulnCheck Advisory: Zebra before 7.0.0 Denial of Service via Quadratic Sighash Computation (third-party-advisory)
Frequently asked questions
- What is CVE-2026-123559?
- CVE-2026-123559 is a high-severity vulnerability in Zcashfoundation Zebra, classified under Inefficient Algorithmic Complexity. CVSS score: 7.5/10. Published 2026-11-08.
- How severe is CVE-2026-123559?
- High severity. CVSS v3 base score is 7.5 out of 10.