CVE-2026-104426 PUBLISHED

Zebra before 6.1.0 Quadratic Complexity DoS via Block Transparent Value Check

Assigner: VulnCheck
Reserved: 02.10.2026 Published: 02.10.2026 Updated: 02.10.2026

Zebra before 6.1.0 contains an inefficient algorithmic complexity vulnerability in remaining_transaction_value that clones the entire block-level spent-UTXO map per transaction during contextual verification. Attackers can mine or seed the mempool with roughly 26,000 minimal single-input transactions in one block, stalling every validating node for over 52 seconds.

CVSS Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS Score: 8.2

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	None	Confidentiality	None
Attack Complexity	High	Integrity	None	Integrity	None
Attack Requirements	Present	Availability	High	Availability	None
Privileges Required	None
User Interaction	None

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 5.9

Attack Vector	Network	Scope	Unchanged
Attack Complexity	High	Confidentiality Impact	None
Privileges Required	None	Integrity Impact	None
User Interaction	None	Availability Impact	High

CVSS 3.1

Product Status

Vendor	ZcashFoundation
Product	zebra
Versions	Default: unaffected affected from 0 to 6.1.0 (excl.) Version 6.1.0 is unaffected

CVE-2026-104426 PUBLISHED

Zebra before 6.1.0 Quadratic Complexity DoS via Block Transparent Value Check

Metrics

Product Status

Credits

References

Problem Types