CVE-2026-86065: Klever-Go

Summary

Klever-Go is the Go implementation of the Klever blockchain protocol. Prior to 1.7.20, the default-open GET /subscribe endpoint in network/api/websocket/routes.go accepts unauthenticated WebSocket clients with permissive origin handling, does not call SetReadLimit to bound message size, and has no live-connection cap. SocketHub.HandleClientInsertion also accepts an unbounded address list that grows addressSubscription, and client.loopIn continues reading without a size limit, allowing one client to grow subscription maps or many clients to retain goroutines, buffered channels, and descriptors. The global HTTP request throttler does not count upgraded live WebSocket connections. Because the REST and WebSocket API runs in the node process, memory or scheduler exhaustion can crash the node and interrupt P2P and consensus participation. This issue is fixed in version 1.7.20.

Severity

High (CVSS 7.5), as scored by NVD.

Weakness

• CWE-770

Recommended actions

• Check whether you run or depend on the affected component and version
• Apply the vendor's fix or mitigation from the references below

Source & attribution

This 0xCERT advisory summarises CVE-2026-86065 from the U.S. National Vulnerability Database: https://nvd.nist.gov/vuln/detail/CVE-2026-86065. Details may change; refer to the original source for the authoritative record.