CVE-2026-55764

Klever-Go is the Go implementation of the Klever blockchain protocol. Prior to 1.7.19, Klever-Go allows a mint-role holder to bypass a finite per-nonce MaxSupply on the semi-fungible token add-quantity path. In core/kapp/systemAccount/systemAcount.go, SFTAddCirculation performed meta.Circulation += amount before evaluating whether Circulation exceeded MaxSupply, without checking for signed int64 overflow. A large positive raw Amount supplied through processSemiFungibleAddQuantity in core/kapp/kda/mint.go can wrap Circulation negative, causing the signed maximum-supply comparison to pass and crediting approximately MaxInt64 units while corrupting the on-chain counter. The fungible path is not affected because its MintedValue <= 0 guard detects the overflow. The correction uses the consensus activation flag FixMarketBuyOverflow. This issue is fixed in version 1.7.19.

  • Published Aug 28, 2026
  • CVSS 8.7 high
  • 0.5% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

CVE-2026-55764 at the National Vulnerability Database