How severe is CVE-2026-4370?

CVE-2026-4370 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-4370 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-4370?

CVE-2026-4370 affects Canonical Juju. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-4370?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2026-4370 have an EU (EUVD) identifier?

Yes. CVE-2026-4370 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17847.

When was CVE-2026-4370 published?

CVE-2026-4370 was published on 2026-04-01 and last updated on 2026-06-17.

CVE-2026-4370

CVE-2026-4370 is a critical-severity vulnerability in Canonical Juju with a CVSS 3.x base score of 10.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-295.

Key facts

Severity: Critical (CVSS 3.x base score 10.0)
EPSS exploit prediction: 0% (30th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-17847
Weakness: CWE-295
Affected product: Canonical Juju
Published: 2026-04-01
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2026-4370?: 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.
How severe is CVE-2026-4370?: CVE-2026-4370 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-4370 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-4370?: CVE-2026-4370 affects Canonical Juju. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-4370?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-4370 have an EU (EUVD) identifier?: Yes. CVE-2026-4370 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17847.
When was CVE-2026-4370 published?: CVE-2026-4370 was published on 2026-04-01 and last updated on 2026-06-17.

References

https://github.com/juju/juju/security/advisories/GHSA-gvrj-cjch-728p

Affected products (1)

cpe:2.3:a:canonical:juju:*:*:*:*:*:*:*:*

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