{"id":"CVE-2026-49343","aliases":["GHSA-fw38-pc54-jvx9","GO-2026-5379"],"url":"https://o3.security/vulnerability/CVE-2026-49343","summary":"Klever-Go KVM: Throttler slot leak in trie account-data sync causes epoch bootstrap / state sync DoS","details":"Klever-Go is the Go implementation of the Klever blockchain protocol. In versions prior to 1.7.18, the account-data trie syncers are vulnerable to a resource-exhaustion flaw that leaks bounded throttler slots on error paths. In syncDataTrie() (in both userAccountsSyncer.go and kappAccountsSyncer.go), StartProcessing() reserves a slot from the NumGoRoutinesThrottler, but the corresponding EndProcessing() is only called on the success path and on the duplicate-root early return. As a result, any error from trie.NewTrie(), trie.NewTrieSyncer(), or trieSyncer.StartSyncing() (including the network-dependent timeout path) permanently consumes one slot for the lifetime of the throttler. An attacker who can repeatedly cause trie-node sync failures or timeouts during bootstrap can exhaust the bounded throttler, after which further account-data trie syncs stop making progress and SyncAccounts() returns a timeout. Because epoch bootstrap in syncUserAccountsState() and syncKappAccountsState() aborts on any such error, this causes bootstrap to fail, a core availability issue affecting fresh, restarting, or resyncing nodes and validators. This issue is fixed in version 1.7.18.","published":"2026-08-07T22:18:18.735Z","modified":"2026-08-15T11:31:24.012022082Z","cvss":{"score":5.9,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":{"score":0.00264,"percentile":0.17849,"asOf":"2026-08-24"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/klever-io/klever-go","fixedVersion":"1.7.18"}],"fix":null,"references":[{"type":"WEB","url":"https://github.com/klever-io/klever-go/releases/tag/v1.7.18"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49343.json"},{"type":"ADVISORY","url":"https://github.com/klever-io/klever-go/security/advisories/GHSA-fw38-pc54-jvx9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-49343"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-15T11:31:24.012022082Z"}}