MQTT Unauthenticated Access (CONNACK Accepted)
mqtt-unauthenticated is a high severity check in the
messaging category, written in yaml.
Its source is templates/messaging/mqtt/mqtt-unauthenticated.yaml in
cert-x-gen-templates.
What it checks
Section titled “What it checks”Detects MQTT brokers that accept unauthenticated CONNECT requests. A CONNACK return code of 0x00 indicates the broker accepted the connection without credentials, which can allow topic enumeration and message injection.
Header
Section titled “Header”| Field | Value |
|---|---|
| Id | mqtt-unauthenticated |
| Severity | high |
| Language | yaml |
| Category | messaging |
| Author | CERT-X-GEN Security Team |
| Template version | 1.0.0 |
| Confidence | 85 |
| CVSS | 7.5 |
| Weakness | CWE-306 |
| Tags | mqtt, mosquitto, iot, unauthenticated, messaging, exposure |
| Target kind | not recorded |
| Oracle | not recorded |
The file declares network, remediation as well. Those are not tabled above; read the
source for what they carry.
References
Section titled “References”Declared in the header. cxg parses @references and then discards it, and
nothing at scan time reads it, so this is the only place the links a
template cites are surfaced.
Run it
Section titled “Run it”To see what the copy on your machine says about itself, and to confirm it is installed at all:
cxg template info mqtt-unauthenticatedThe id it prints is the one to pass anywhere a template is selected. See
cxg template for the rest of
the subcommand, Scan a target for running
a scan, and
A match is not a finding for how
to read what comes back.
Related
Section titled “Related”- Template catalog is the whole corpus.
- messaging is the rest of this category.
- Templates by weakness class groups checks by the defect they look for.
- Contribute a template is the route from a check you needed and could not find to a merged one.