CVE-2026-86064 Klever-Go: /log controls global node logging
Unauthenticated remote attackers can modify global log settings and access live process logs via the /log WebSocket route in Klever-Go nodes.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-86064?
CVE-2026-86064 is a high-severity missing authorization vulnerability in klever-io klever-go, published on 23 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Klever-Go is the Go implementation of the Klever blockchain protocol. Prior to 1.7.20, the default-open GET /log WebSocket route configured in config/node/api.yaml and registered by network/api/api.go does not require authentication. The first client message is parsed as a logger Profile in network/api/logs/logSender.go and applied process-wide through Profile.Apply, allowing a remote client to change global log levels and formatting options until the connection closes. The same connection is registered as a log observer and can receive live process logs. An attacker can suppress normal logs, increase verbosity, distort operator visibility, and access operational information without credentials. This issue is fixed in version 1.7.20.
Which versions are affected by CVE-2026-86064?
3 open source packages ship an affected version, including github.com/klever-io/klever-go.
| Package | Affected | Fixed in |
|---|---|---|
github.com/klever-io/klever-go Go | All versions | 1.7.20 |
github.com/klever-io/klever-go Go | All versions | 1.7.20 |
github.com/klever-io/klever-go Go | All versions | 1.7.20 |
How do I fix CVE-2026-86064?
Upgrade github.com/klever-io/klever-go to 1.7.20 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-86064 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-86064 exists.
Sources
Also known as GHSA-9v8p-frvj-2pcm, GO-2026-6583.