What it is
Cloud object storage services—Amazon S3, Azure Blob Storage, Google Cloud Storage—are widely used to host backups, logs, static assets, and data lakes. Misconfiguration occurs when buckets or containers are inadvertently granted public read/write access, or when identity and access management (IAM) policies are overly permissive. Attackers and opportunistic crawlers continuously scan cloud storage for public buckets and exposed files.
Commonly exposed assets include personally identifiable information (PII), credentials, source code, and proprietary data. Missing encryption, versioning, or lifecycle policies can compound the impact by leaving sensitive archives accessible indefinitely.
Why it matters
High-profile breaches often stem from exposed cloud storage, resulting in regulatory fines, brand damage, and loss of trust. Because cloud consoles make permission changes easy, human error combined with weak governance frequently leads to leaks. Many compliance frameworks require demonstrable control over cloud data access, so misconfigurations quickly translate into audit issues.
How to reduce risk
- Deny public access by default and enforce least-privilege IAM policies.
- Use automated cloud security posture management (CSPM) tools to detect and remediate open buckets.
- Encrypt objects at rest and require private network (VPC) access where possible.
- Apply versioning and lifecycle policies to minimize the retention of sensitive data.
- Audit access logs and alert on anomalous reads or wide permission changes.