CVE-2026-58262 (GCVE-0-2026-58262)

Vulnerability from cvelistv5 – Published: 2026-08-07 22:00 – Updated: 2026-08-12 22:15
VLAI
Title
Klever-Go: PubKeysBitmap padding bits bypass the BLS signature quorum
Summary
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.
Severity
7.1 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-12 22:08 UTC
CWE
  • CWE-345 - Insufficient Verification of Data Authenticity
  • CWE-347 - Improper Verification of Cryptographic Signature
Assigner
References
Impacted products
Vendor Product Version
klever-io klever-go Affected: < 1.7.20
Create a notification for this product.
Show details on NVD website
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