Zebra before 6.3.0 contains a protection mechanism failure that allows unauthenticated peers to evade misbehavior scoring by supplying invalid gossiped blocks. The inbound cleanup step wrongly downcasts RouterError to VerifyBlockError and discards the score, so attackers can repeatedly force block download and Equihash verification without being banned.

CVSS Details

CVSS 4.0 Base Score: 6.9 (MEDIUM)
CVSS 4.0 Vector: (CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X)
CVSS 3.1 Base Score: 5.3
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)

Prioritize with Active Threat Intelligence

With curated Threat Intelligence, you can see which vulnerabilities truly put you at risk, prioritize what matters most, and act before attackers do.

Explore Intelligence Hub

MDR Buyer's Guide

Global Threat Landscape Report

Grow your business

CVSS Details

Prioritize with Active Threat Intelligence

MDR Buyer's Guide

Global Threat Landscape Report

Grow your business

CVE-2026-104420: Incorrect Type Conversion or Cast

CVSS Details

Prioritize with Active Threat Intelligence