Top 10 AWS Security Misconfigurations That Could Ruin Your Week

Security breaches don’t always come from advanced hackers. Sometimes, they come from simple mistakes—left open for anyone to find.

At Ananta Cloud, we've audited dozens of AWS environments. And we’ve seen the same terrifying patterns again and again: small misconfigurations that seem harmless… until they open the door to data leaks, privilege escalations, or full-blown compromises.

Here are the Top 10 AWS security misconfigurations that could ruin your week—along with how to fix them before they ruin your month (or year).

Public S3 Buckets (Yes, Still.)

You’ve heard this before—but it still happens every week. An S3 bucket accidentally set to public-read or public-list can expose logs, customer data, or sensitive backups.

What to check:

• S3 bucket policies

• Block public access settings

Fix:

• Enable Block All Public Access

• Use S3 Access Analyzer to monitor exposure

IAM Users with Admin Access

An IAM user with full admin rights is a recipe for disaster—especially if the credentials are compromised.

What to check:

• IAM users with AdministratorAccess policy

• Long-lived access keys

Fix:

• Use IAM roles, not users

• Rotate and disable inactive access keys

• Apply least privilege principle

Overly Broad IAM Policies

“Action:, Resource:” = instant nightmare. This kind of wildcard policy effectively gives a user the keys to your entire AWS kingdom.

What to check:

• Custom IAM policies with wildcards

• Managed policies applied to multiple roles

Fix:

• Restrict actions and resources explicitly

• Use Access Advisor and Policy Simulator to test

Unrestricted Security Groups

Allowing 0.0.0.0/0 to inbound on ports like 22 (SSH), 3389 (RDP), or 80/443 (web) is asking for trouble.

What to check:

• Inbound rules on critical ports

• Ports open to the world

Fix:

• Use bastion hosts, VPNs, or AWS SSM Session Manager

• Restrict IP ranges to known networks

No MFA for Root Account

The AWS root account is your nuclear button. If it’s not protected with MFA, you’re just hoping no one gets in.

What to check:

• MFA enabled for root user

• Root access activity in CloudTrail

Fix:

• Enable MFA immediately

• Store root credentials securely and avoid daily use

Lambda Functions with Excessive Permissions

It’s common to give Lambda functions more permissions than they need “just to make it work.” Bad idea.

What to check:

• Execution roles assigned to Lambda functions

• Use of * actions in Lambda policies

Fix:

• Apply least privilege IAM roles

• Break permissions down per function

Disabled or Missing CloudTrail

No logging = no forensics. If CloudTrail isn’t enabled in all regions, you won’t know what hit you when something goes wrong.

What to check:

• Is CloudTrail enabled across all regions?

• Are logs being stored securely?

Fix:

• Enable multi-region CloudTrail

• Store logs in secure, encrypted S3 buckets

EC2 Instances Without Patching or Hardening

Unpatched EC2 instances with open ports are low-hanging fruit for attackers.

What to check:

• OS patch levels

• Public IPs attached to instances

Fix:

• Automate patching with SSM Patch Manager

• Harden AMIs and use private subnets for EC2 where possible

Unused Access Keys Still Active

Inactive or forgotten access keys hanging around in your account are a common vector for compromise—especially if they’ve been leaked in Git or logs.

What to check:

• IAM access keys older than 90 days

• Keys with no activity

Fix:

• Rotate keys regularly

• Remove unused keys

• Use temporary credentials via IAM roles

Lack of Guardrails (No SCPs, No Config, No Alerts)

No Service Control Policies, no AWS Config, and no CloudWatch or Security Hub alerts = you're flying blind.

What to check:

• SCPs in place for organizational units

• AWS Config rules for compliance

• Alerting pipelines to Slack/Email/SIEM

Fix:

• Implement guardrails using AWS Organizations + SCPs

• Turn on AWS Config and Security Hub

• Route alerts via SNS to teams that will act

Final Thoughts: Scared Yet? Good.

These misconfigurations are shockingly common—even in production environments. The good news? They’re all fixable with a weekend of cleanup or a solid DevSecOps strategy.

At Ananta Cloud, we help companies lock down their AWS environments, identify security gaps, and build a culture of cloud security by design.

Want a free security check-up?

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