SECURELYN

CVE-2026-85724

Moquette is a lightweight Java MQTT broker. Prior to 0.18.1, when pattern-based ACL rules are configured, AuthorizationsCollector.canDoOperation substitutes client ID and username values directly into rules containing %c or %u and then treats the result as an MQTT topic filter. A client that uses + or # in either identity can broaden the substituted filter and gain cross-tenant read and write access. A # identity can also produce an invalid filter that triggers a NullPointerException in Topic.match and disrupts session processing. This issue is fixed in version 0.18.1.

Scores

9.6
CVSS 9.6 out of 10, critical severity.
0.3%
EPSS 0.3% chance of exploitation in the next 30 days.

The facts

Published
23 September 2026
Last changed
25 September 2026
NVD status
Analyzed
Severity
Critical, CVSS 9.6 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
Weakness
Affects
  • moquette moquette
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.3% chance of exploitation activity in the next 30 days (percentile 18).

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References