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AWS Security Hub · ECS

ECS.9: A task definition has no logging configuration

Written and reviewed by Emnode · Last reviewed

What does AWS Security Hub ECS.9 check?

ECS.9 flags the latest active revision of a task definition that has no logConfiguration defined, or where any container's logDriver is null. It wants every container wired to a log destination before it ever runs.

Why does ECS.9 matter?

A logless container is operationally and forensically blind. When a service throws a 500 at 3am, the on-call engineer has nothing to read, so mean-time-to-resolution stretches from minutes to hours as every theory has to be reproduced live. The same gap means a security incident leaves no trail and an audit has nothing to sample — ECS.9 maps to a stack of NIST 800-53 audit-and-accountability controls for exactly that reason.

How do I fix ECS.9?

  1. Add a logConfiguration block to every container, typically with the awslogs driver pointing at a CloudWatch Logs group.
  2. Pre-create the log group (or set awslogs-create-group) and grant the task execution role logs:CreateLogStream and logs:PutLogEvents.
  3. Register the new revision and redeploy, then confirm log streams appear.

Remediation script · bash

# Inventory: flag containers running as root or with a writable root filesystem.
for fam in $(aws ecs list-task-definition-families --status ACTIVE \
    --query 'families[]' --output text); do
  aws ecs describe-task-definition --task-definition "$fam" \
    --query "taskDefinition.containerDefinitions[?user==null || user=='root' || user=='0' || readonlyRootFilesystem!=\`true\`].{Family:'$fam',Name:name,User:user,ReadOnly:readonlyRootFilesystem}" \
    --output text
done

# Harden at the source. Dockerfile:
#   RUN addgroup -S app && adduser -S -G app appuser
#   USER appuser
# Task definition: non-root user, read-only root with one narrow tmpfs, secrets via ARN.
#   "user": "1000:1000",
#   "readonlyRootFilesystem": true,
#   "mountPoints": [{ "sourceVolume": "scratch", "containerPath": "/tmp", "readOnly": false }],
#   "secrets": [{ "name": "DB_PASSWORD",
#     "valueFrom": "arn:aws:secretsmanager:us-east-1:123456789012:secret:prod/checkout/db-AbCdEf" }]

# Register the hardened revision and roll it out (tasks only update on redeploy).
aws ecs register-task-definition --cli-input-json file://checkout-api-hardened.json
aws ecs update-service --cluster prod --service checkout-api \
  --task-definition checkout-api --force-new-deployment

Full walkthrough (console steps, edge cases and verification) in the lesson Harden ECS container workloads.

Part of the learning path Lock down access
  • ECS.2 An ECS service auto-assigns public IPs to tasks
  • ECS.3 A task definition shares the host PID namespace
  • ECS.4 A container runs in privileged mode
  • ECS.5 A container has a writable root filesystem
  • ECS.8 Secrets are passed as plaintext container env vars
  • ECS.10 Fargate services should run latest platform version
  • ECS.12 ECS clusters should use Container Insights
  • ECS.16 An ECS task set auto-assigns public IPs
  • ECS.18 ECS task defs should encrypt EFS volumes in transit
  • ECS.19 Capacity providers managed termination protection
  • ECS.20 Linux containers should run as non-root users
  • ECS.21 Windows containers should run as non-admin users