CVE-2026-86065

Klever-Go: Unauthenticated WebSocket /subscribe: no read-size limit, no connection cap, permissive origin -> remote node memory/goroutine exhaustion (DoS)

State
Published
Severity
7.5 High
Published
Sep 23, 2026
Updated
Sep 29, 2026
Reserved
Sep 4, 2026

Read the record on cve.org

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.

Scores

CVSSScoreVectorSource
3.17.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HGitHub_M

Weaknesses

  • CWE-770 Allocation of Resources Without Limits or Throttling

Affected Products

ProductVersions
klever-goklever-io
  • < 1.7.20Affected

References

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