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

No history.

Information

Published : 2026-08-07 22:16

Updated : 2026-09-09 20:55

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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