CVE-2026-58262

Klever-Go is the Go implementation of the Klever blockchain protocol. Prior to 1.7.20, header signature verification counts the unused padding bits of the PubKeysBitmap toward the two-thirds validator quorum. These padding bits do not correspond to any validator and are ignored by the actual BLS aggregate-signature check, so a malicious or compromised block producer can set them to reach the required quorum while gathering fewer genuine validator signatures than the protocol demands. As a result, nodes that import or intercept the header accept it as correctly signed without a real two-thirds quorum, weakening consensus safety and undermining finality. This issue is fixed in version 1.7.20.

CVSS

No CVSS.

References

Link	Resource
https://github.com/klever-io/klever-go/commit/a11cb28e495e608d8034dbe83a91e89d0c68e0f7
https://github.com/klever-io/klever-go/security/advisories/GHSA-f9h7-4mmq-vgcq

Configurations

No configuration.

History

23 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) Klever-Go es la implementación en Go del protocolo de cadena de bloques Klever. Antes de la versión 1.7.20, la verificación de la firma de la cabecera cuenta los bits de relleno no utilizados de PubKeysBitmap para el quórum de validadores de dos tercios. Estos bits de relleno no corresponden a ningún validador y son ignorados por la verificación real de la firma agregada BLS, por lo que un productor de bloques malicioso o comprometido puede configurarlos para alcanzar el quórum requerido mientras reúne menos firmas de validadores genuinas de las que exige el protocolo. Como resultado, los nodos que importan o interceptan la cabecera la aceptan como correctamente firmada sin un quórum real de dos tercios, debilitando la seguridad del consenso y socavando la finalidad. Este problema se corrige en la versión 1.7.20.

Information

Published : 2026-08-07 22:16

Updated : 2026-10-24 16:10

NVD link : CVE-2026-58262

Mitre link : CVE-2026-58262

CVE.ORG link : CVE-2026-58262

JSON object : View

Products Affected

No product.

CWE

CWE-345

Insufficient Verification of Data Authenticity

CWE-347

Improper Verification of Cryptographic Signature

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