Common Cloud Misconfigurations

Misconfigurations are the leading cause of cloud data breaches. Unlike traditional on-prem vulnerabilities that require exploiting software bugs, cloud misconfigurations are often self-inflicted and trivially exploitable by anyone on the internet.

S3 buckets with public read access expose any stored data to the internet. Attackers scan for open buckets using tools like GrayhatWarfare. Prevention: S3 Block Public Access at account level, S3 Object Ownership enabled, bucket policies audited regularly.

Security groups with 0.0.0.0/0 on port 22 (SSH), 3389 (RDP), or administrative ports create massive attack surfaces. Restrict inbound rules to specific CIDR ranges. Use AWS Systems Manager Session Manager instead of open SSH.

Accidentally sharing RDS snapshots publicly exposes entire database contents. Automated snapshots default to private, but manual shares can expose sensitive data. Audit snapshot visibility with describe-db-snapshots --include-public.

Developers commit AWS access keys, database passwords, and API tokens to Git repositories. Attackers scan GitHub/GitLab with tools like TruffleHog and GitLeaks. Prevention: use secrets managers, git-secrets pre-commit hooks, and org-wide secret scanning.

Without CloudTrail enabled in all regions, API calls go unrecorded. Attackers exploit logging gaps to operate undetected. Enable CloudTrail org-wide, send logs to a separate security account S3 bucket with S3 Object Lock for tamper protection.

IMDSv1 allows any process on an EC2 instance to query the metadata service without authentication, enabling SSRF attacks to steal instance credentials. Enforce IMDSv2 (token-required) on all instances to require session-oriented authentication.

Security groups typically allow all outbound traffic. This enables data exfiltration and C2 communication from compromised instances. Use egress filtering via security groups, NACLs, or a firewall appliance to restrict outbound connections to known destinations.

Kubernetes dashboards, Elasticsearch clusters, MongoDB instances, and Jupyter notebooks left exposed without authentication on public IPs are routinely compromised. Every management interface must require authentication and be network-restricted.

S3 data events and CloudTrail management events alone miss object-level actions (GetObject, PutObject). Enable S3 Server Access Logging and CloudTrail S3 data events for sensitive buckets to detect data exfiltration attempts.

AWS Config rules with automatic remediation (via SSM Automation documents or Lambda) can auto-remediate violations: make buckets private, close security group rules, or quarantine credentials — reducing exposure time from days to minutes.

What is the primary risk of leaving IMDSv1 enabled on EC2 instances?

Cloud misconfigurations — public buckets, permissive security groups, hardcoded credentials, and missing logs — are the most common cause of cloud breaches. Automated scanning, enforced guardrails, and continuous monitoring are essential defensive measures.