If you are a cloud professional, security is not optional it's essential. Whether you are managing EC2 instances, S3 buckets, or databases in AWS, you need to ensure you are protected from malicious activity, misconfigurations, and potential breaches. That’s where AWS GuardDuty introduced
In this article, we will explore, what GuardDuty is, why we need it, and exactly how to enable it with just a few clicks.
What Is AWS GuardDuty?
AWS GuardDuty is a threat detection service that continuously monitors your AWS accounts, workloads, and data for suspicious activity. It uses machine learning, anomaly detection, and threat intelligence to identify potential threats.
In short, GuardDuty acts like a security camera for your AWS environment- always watching, always alert.
Some of the threats GuardDuty can detect include - Unusual API calls, Unauthorized access to your resources, Data exfiltration attempts, Communication with known malicious IPs or domains.
Why we should Use GuardDuty?
Following are some quick, real time reasons to enable GuardDuty:
- No agents required: Unlike many security tools, GuardDuty works without having agent installed or manage software.
- Real time detection: Alerts are generated in near real time.
- Covers multiple AWS services: It integrates with CloudTrail, VPC Flow Logs, and DNS logs automatically.
- Low maintenance: It’s fully managed by AWS, so no manual rule tuning or signature updates.
Let’s dive into the actual step by step process to enable AWS GuardDuty.
Prerequisite: You need administrator or relevant IAM permissions (guardduty:*) to perform these steps.
Step 1: Go to the GuardDuty Console : Sign in to your AWS Management Console.
In the top search bar, type "GuardDuty" and click on the service when it appears.
You will land on the GuardDuty dashboard.
Step 2: Enable GuardDuty :
If this is your first time, you will see a welcome page with an “Enable GuardDuty” button. So click Enable GuardDuty.
That’s it! GuardDuty will now start analyzing CloudTrail logs, VPC Flow Logs, and DNS query logs automatically.
Note: GuardDuty is region-specific. You will need to enable it in each AWS region you want to monitor.
Step 3: Set Up Multi-Account Monitoring (optional)
If you are managing multiple AWS accounts (like an organization), you can set up GuardDuty in the master account and invite member accounts and to do this.
In the GuardDuty dashboard, go to Settings → Accounts. Click Add accounts and enter the AWS account IDs of the member accounts.
Note: You can add individual accounts by choosing Add Account, or you can add a list of accounts by choosing Upload List e.g.; (.csv).
Once invited, the member accounts need to accept the invitation.
After the member account owner accepts the invitation, the Status in the master account is changed to "Monitored". Status helps you track the status of each AWS account that you invite.
Once you enabled GuardDuty on the member account, all findings will be forwarded to the master account. You can now monitor the findings about GuardDuty member accounts from the GuardDuty console in the master account.
This allows you to centrally monitor threats across all accounts.
How to View and Understand the Findings.
Once enabled, GuardDuty starts generating findings these are the alerts you should monitor and how you can view them.
In the GuardDuty console, go to Findings in the left-hand menu. You will see a list of security findings, each with:
Title: A short description (e.g., “[SAMPLE] Backdoor:EC2/C&CActivity.B”)
Severity: Low, Medium, or High
Resource affected
Details: IP addresses, location, event time, and more
Click on any finding to view in-depth details.
Note: We can set up SNS notifications or integrate with AWS Security Hub to centralize alerts.
- Detecting brute force attacks on EC2 instances.
- Identifying unauthorized access from unfamiliar IPs.
- Tracking lateral movement within VPCs.
- Monitoring S3 bucket access for unusual activity.