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CVE-2026-123554

8.7 highEPSS 0.4%

High (8.7) in zcashfoundation zebra. EPSS 0.4% estimated probability of exploitation activity in the next 30 days.

On this page
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.

Severity

CVSS 4.0

8.7 high
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

CVSS 3.1

7.5 high
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
0.4% estimated probability of exploitation activity in the next 30 days; 38th percentile. Scored 2026-11-10. A forecast for this CVE across the internet, not for your own systems.
CISA's assessment (SSVC)
Exploitation: none · Automatable: yes · Technical impact: partial, assessed 2026-11-09. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
CWE
CWE-407 Inefficient Algorithmic Complexity
Published
Modified
NVD analysis
Deferred: the NVD does not plan to analyze it
Record from
the NVD, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
ZcashFoundation zebrafrom 6.4.0 before 7.0.0

References

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