CVE-2026-104423

Zebra (zebrad) before 6.2.1 contains an asymmetric resource consumption vulnerability that allows unauthenticated peers to stall block verification by pushing V6 mempool transactions with invalid Halo2 proofs. Attackers can flood the shared unprioritized Halo2 verification queue with zero-fee transactions carrying zero-filled Orchard and Ironwood proofs, causing nodes to fall behind the chain tip.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-2p4c-3q4q-p463
https://www.vulncheck.com/advisories/zebra-before-6.2.1-denial-of-service-via-uncapped-v6-shielded-proof-verification

Configurations

No configuration.

History

02 Oct 2026, 12:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-02 12:17

Updated : 2026-10-02 17:59

NVD link : CVE-2026-104423

Mitre link : CVE-2026-104423

CVE.ORG link : CVE-2026-104423

JSON object : View

Products Affected

No product.

CWE

CWE-405

Asymmetric Resource Consumption (Amplification)

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