CVE-2026-58262
HIGH
MEDIUM
Priority: 0.01
BB Relevance:
64/100
Published: 2026-08-07
Modified: 2026-10-24
First seen: 2026-10-29
Status: active
Attack Surface
Network
Low Complexity
No Interaction
Integ. Impact
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
Low
UI:
None
S:
X
AT:
None
VC:
None
VI:
High
VA:
None
Description
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.