MSK Client Authentication Missing

What this rule checks

Detects MSK clusters without client authentication or that allow unauthenticated access.

How to fix it

1. 1Enable SASL/SCRAM, IAM auth, or mTLS in ClientAuthentication
2. 2Disable Unauthenticated access

import { aws_ec2 as ec2, aws_msk as msk } from 'aws-cdk-lib';

const vpc = new ec2.Vpc(this, 'Vpc');

new msk.CfnCluster(this, 'Cluster', {
  clusterName: 'orders',
  kafkaVersion: '3.6.0',
  numberOfBrokerNodes: 2,
  brokerNodeGroupInfo: {
    instanceType: 'kafka.m5.large',
    clientSubnets: vpc.privateSubnets.map((s) => s.subnetId),
  },
  clientAuthentication: {
    unauthenticated: { enabled: true },
  },
});

import { aws_ec2 as ec2, aws_msk as msk } from 'aws-cdk-lib';

const vpc = new ec2.Vpc(this, 'Vpc');

new msk.CfnCluster(this, 'Cluster', {
  clusterName: 'orders',
  kafkaVersion: '3.6.0',
  numberOfBrokerNodes: 2,
  brokerNodeGroupInfo: {
    instanceType: 'kafka.m5.large',
    clientSubnets: vpc.privateSubnets.map((s) => s.subnetId),
  },
  clientAuthentication: {
    unauthenticated: { enabled: false },
    sasl: { iam: { enabled: true } },
  },
});

CDK Insights pinpoints the exact file and line in your CDK source for every finding, so you can jump straight to the fix.

Affected resource types

Intentional? Suppress this finding

Sometimes a flag is deliberate — a genuinely public endpoint, say. You can dismiss msk-client-authentication-missing and the reason is kept in the report, not silently hidden.

In .cdk-insights.json:

{
  "ignoreRules": [
    { "id": "msk-client-authentication-missing", "reason": "Why this is intentional" }
  ]
}

Or inline in your CDK code:

Validations.of(scope).acknowledge({
  id: 'cdk-insights::msk-client-authentication-missing',
  reason: 'Why this is intentional',
});

Use the rule ID msk-client-authentication-missing shown above — not the CDK-* ID from SARIF / GitHub code scanning. To dismiss every finding on one construct instead, use ignorePaths. Suppression docs →

More MSK rules