CVE-2026-123559

HIGH 7.5

Zebra before 7.0.0 Denial of Service via Quadratic Sighash Computation

CVSS Score

7.5

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-407
Vendor	zcashfoundation
Product	zebra
Published	Nov 8, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Affected Versions

ZcashFoundation / zebra

0 < 7.0.0

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-j4cw-58mj-7w6v vulncheck.com: https://www.vulncheck.com/advisories/zebra-before-7.0.0-denial-of-service-via-quadratic-sighash-computation

Credits

🔍 asafmod mpguerra conradoplg upbqdn