Skip to main content
VulnerabilityPublished Updated

CVE-2026-4370: Canonical Juju · Improper Certificate Validation

Affects Canonical JujuSource CVE Database V5

0
Compare

Not known to be exploited · CVSS 10.0 Critical : upgrade to 4.0.4 or 3.6.20 as a priority.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score
10.0Critical
How severe the flaw is on the 0–10 CVSS scale.

Contested

Critical score, yet low EPSS after six months
EPSS
0.3% chance of exploitation in 30 days – higher than 32% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available – fixed in 4.0.4, 3.6.20
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 1 Apr 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponized: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.

What to do

Upgrade Juju and juju to 4.0.4 or 3.6.20.

Affected software

ProductAffectedFixed in
CanonicalJujuAffected
  • >=4.0 <4.0.4
Fixed in
  • 4.0.4
CanonicalJujuAffected
  • >=3.2.0 <3.6.20
Fixed in
  • 3.6.20
GitHubjuju/jujupkg:github/juju/jujuOther threatsAffected
  • =3.2.0
  • =4.0
Fixed in–
GitHubjujupkg:github/jujuOther threatsAffected
  • >=3.2.0 <3.6.20
  • >=4.0 <4.0.4
Fixed in
  • 3.6.20
  • 4.0.4

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

If you cannot patch yet, restrict network access to the Juju controller's Dqlite port to trusted hosts only to reduce exposure.

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.

References

Community reviews

Loading reviews…