As reported by Security Affairs, the Ransomnews research team has published findings from their Cloud Exposure Index showing 484,142 publicly listable cloud storage buckets containing roughly 18 billion files. The research methodology is notable for its restraint—researchers used only bucket names, file extensions, counts, and last-modified timestamps without opening any files—yet still surfaced enough signal to identify where sensitive material concentrates.
The headline number sounds alarming, but context matters: many of these buckets are intentionally public, hosting CDN assets, open datasets, and podcast archives. The real concern is the subset that should never have been listable—buckets containing backups, exports, payroll records, credentials, and database dumps. That is where the actual breach risk lives.
Azure's Overrepresentation in Operational Data
Amazon S3 accounts for 72% of exposed buckets, roughly proportional to its market share. The more revealing finding is Azure Blob's disproportionate presence among buckets named for sensitive operational data:
Given Azure Blob holds only 14.2% of total exposed buckets, this skew—2.5 to 3.6 times above its baseline—is statistically significant and points to a systemic issue in how Azure storage accounts are configured by default or provisioned through automated workflows. The fact that dev/test/staging buckets sit at or below Azure's baseline suggests the problem is not platform-wide but specific to operational data pipelines, likely tied to how Azure Storage Account tools, ARM templates, or IaC modules handle access policies.
Credential Exposure: The .env Problem Persists
The finding that 321,058 credential and key-related files are exposed—67% of which are .env files modified in 2026—tells us that developers are still deploying environment configuration files to cloud storage without access controls. This is a well-understood misconfiguration that has persisted for years despite repeated warnings from cloud providers and security researchers.
Exposed .env files are not a new problem, but the fact that two-thirds were modified this year means teams are actively creating new exposures, not just inheriting legacy ones. This is a deployment pipeline problem, not an awareness problem.
Why This Matters for Defenders
The Ransomnews Index quantifies what security teams have long suspected: cloud storage misconfiguration remains endemic, and the problem is growing rather than shrinking. Several implications stand out:
- Enumeration is trivial. Attackers don't need to breach anything—they can use the same public search engines the researchers used to identify targets of interest.
- Naming conventions leak intent. Bucket names containing "backup," "payroll," or "export" serve as a beacon for attackers prioritizing high-value targets.
- Quarterly tracking enables trend analysis. Ransomnews plans to rerun this quarterly, which means organizations that don't remediate will show up repeatedly—a reputational risk on top of the security risk.
Shield53 Recommendations
- Audit immediately. Run CSPM tools (e.g., AWS Access Analyzer, Azure Storage Firewalls and Virtual Networks, or third-party platforms like Wiz, Orca, or Prowler) to identify all publicly accessible buckets in your environment. Don't assume your cloud provider's defaults are safe.
- Block public access by default. Enable Block Public Access at the account level on AWS S3. Use Azure Storage Firewalls to restrict access to selected virtual networks and IP addresses. Apply similar restrictions on GCS buckets.
- Scan for .env and credential files. Deploy automated scanning across all storage buckets for files with .env, .key, .pem, .pfx, or similar extensions. Rotate any credentials found in storage immediately.
- Rename operational buckets. While security through obscurity is insufficient, removing obvious keywords like "backup" and "payroll" from bucket names reduces the signal-to-noise ratio for automated discovery tools.
- Enforce via IaC. Add policy-as-code checks (OPA, Checkov, tfsec) to CI/CD pipelines that fail builds when storage resources lack explicit private access controls.
- Implement continuous monitoring. One-time audits decay quickly. Set up automated alerting for any bucket that transitions from private to public, and require approval workflows for exceptions.
The Ransomnews Index is a useful contribution to the field, but its real value will come from whether organizations use it as a catalyst for remediation rather than a passing headline. The tools to fix this exist today. The gap is in operational discipline—enforcing policies consistently across teams, environments, and providers. Until that gap closes, these numbers will only grow.
