Is there a public exploit for CVE-2026-123559?

No public exploit for CVE-2026-123559 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-123559?

CVE-2026-123559 scores CVSS 8.7 (v4.0), rated high.

What does CVE-2026-123559 affect?

CVE-2026-123559 affects ZcashFoundation zebra.

8.7 High

Zebra before 7.0.0 contains an inefficient algorithmic complexity vulnerability that allows unauthenticated peers to exhaust verification…

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.

Assessment

CVSS: 8.7 (v4.0)
Severity: High
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 8 November 2026
Last updated: 8 November 2026
Affected: ZcashFoundation · zebra
Assigner: VulnCheck

CVSS vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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