CVE-2026-86065: klever-io klever-go

Vulnerability summary

CVE-2026-86065 is a high (CVSS 7.5) vulnerability in klever-io klever-go. EPSS estimates a 0.35% chance of exploitation in the next 30 days, higher than 27.3% of scored vulnerabilities.

Timeline

1. 23-09-2026
   PublishedVulnerability first disclosed.
2. 29-09-2026
   Last modifiedVulnerability information updated.

Description

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.

• CWE-770Allocation of Resources Without Limits or ThrottlingThe product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.