{"id":"CVE-2026-55764","state":"PUBLISHED","title":"Klever-Go: SFT add-quantity `int64` overflow bypasses a finite per-nonce MaxSupply","description":"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.","publishedAt":"2026-08-28T22:08:27.196Z","updatedAt":"2026-08-31T18:24:52.989Z","severity":{"score":8.7,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["klever-io klever-go"],"affected":[{"vendor":"klever-io","product":"klever-go","versions":[{"version":"< 1.7.19","status":"affected"}]}],"references":["https://github.com/klever-io/klever-go/security/advisories/GHSA-mrpp-v6pg-p54x","https://github.com/klever-io/klever-go/commit/8bcc600b0ac88070740c63c7ce1c8a968dd85251","https://github.com/klever-io/klever-go/releases/tag/v1.7.19"],"weaknesses":["CWE-190"],"ingestedAt":"2026-10-29T20:12:24.861Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/55xxx/CVE-2026-55764.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-55764","state":"PUBLISHED","datePublished":"2026-08-28T22:08:27.196Z","dateUpdated":"2026-08-31T18:24:52.989Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-17T14:34:51.880Z"},"containers":{"cna":{"title":"Klever-Go: SFT add-quantity `int64` overflow bypasses a finite per-nonce MaxSupply","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"klever-io","product":"klever-go","versions":[{"version":"< 1.7.19","status":"affected"}]}],"references":[{"url":"https://github.com/klever-io/klever-go/security/advisories/GHSA-mrpp-v6pg-p54x","name":"https://github.com/klever-io/klever-go/security/advisories/GHSA-mrpp-v6pg-p54x","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/klever-io/klever-go/commit/8bcc600b0ac88070740c63c7ce1c8a968dd85251","name":"https://github.com/klever-io/klever-go/commit/8bcc600b0ac88070740c63c7ce1c8a968dd85251","tags":["x_refsource_MISC"]},{"url":"https://github.com/klever-io/klever-go/releases/tag/v1.7.19","name":"https://github.com/klever-io/klever-go/releases/tag/v1.7.19","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":8.7,"baseSeverity":"HIGH","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-190","lang":"en","description":"CWE-190: Integer Overflow or Wraparound","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-08-28T22:08:27.196Z"},"source":{"advisory":"GHSA-mrpp-v6pg-p54x","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/klever-io/klever-go/security/advisories/GHSA-mrpp-v6pg-p54x","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-31T18:23:51.686866Z","id":"CVE-2026-55764","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-31T18:24:52.989Z"}}]}}}