CVE-2026-104420

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 v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-8hh2-hrf2-cqf4
https://www.vulncheck.com/advisories/zebra-before-6.3.0-peer-misbehavior-ban-bypass-via-gossiped-blocks

Configurations

No configuration.

History

02 Oct 2026, 12:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-02 12:17

Updated : 2026-10-06 03:17

NVD link : CVE-2026-104420

Mitre link : CVE-2026-104420

CVE.ORG link : CVE-2026-104420

JSON object : View

Products Affected

No product.

CWE

CWE-704

Incorrect Type Conversion or Cast

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