Vulnerability · Published Apr 1, 2026 · Assigned by canonical
CVE-2026-4370Improper TLS Client/Server authentication and certificate verification on Database Cluster
Critical 10.0
In plain English
A critical-severity improper certificate validation in Juju from Canonical. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 33% of all known vulnerabilities).
Official description
A vulnerability was identified in Juju from version 3.2.0 until 3.6.19 and from version 4.0 until 4.0.4, where the internal Dqlite database cluster fails to perform proper TLS client and server authentication. Specifically, the Juju controller's database endpoint does not validate client certificates when a new node attempts to join the cluster. An unauthenticated attacker with network reachability to the Juju controller's Dqlite port can exploit this flaw to join the database cluster. Once joined, the attacker gains full read and write access to the underlying database, allowing for total data compromise.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/juju/juju | no fix listed | GHSA-gvrj-cjch-728p |
| Go | github.com/juju/juju | no fix listed | GO-2026-5405 |
Affected products (as reported)
Weakness: CWE-295, CWE-306 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H