CVE-2026-123554
Published:November 08, 2026
Updated:November 09, 2026
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.
Affected Packages
https://github.com/ZcashFoundation/zebra.git (GITHUB):
Affected version(s) >=v6.4.0 <v7.0.0 || =v7.0.0-rc.0 <v7.0.0Fix Suggestion:
Update to version v7.0.0zebra-chain (RUST):
Affected version(s) >=13.0.0 <15.0.0 || =14.0.0 <15.0.0Fix Suggestion:
Update to version 15.0.0Related Resources (5)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.7
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Weakness Type (CWE)
Inefficient Algorithmic Complexity
EPSS
Base Score:
0.43