Cloud Security Validation — Scope Before Access
Cloud Security Validation — Scope Before Access
Important
Use only an owned disposable tenant, account, subscription, project, and seeded identity named in written authorization. Confirm caller identity, region, cost ceiling, audit-log readiness, allowed mutations, proof limit, stop authority, and cleanup before any provider API call. Use Cloud Validation Catalog.
Cloud testing starts from a customer-provided or lab-seeded identity and an explicit authorization boundary. If credentials or access are not supplied, stop and resolve the scope; do not acquire real credentials independently.
Credential Acquisition Techniques
Common methods to obtain credentials include:
- User Enumeration: Identifying valid usernames by probing authentication mechanisms. Differences in server responses during login attempts can reveal valid usernames.
- Public Exposure: Searching for exposed secrets such as access keys and tokens in public repositories or misconfigured storage services.
- Exploiting Vulnerabilities: Leveraging web application vulnerabilities (e.g., Server-Side Request Forgery (SSRF)) to access internal services and extract credentials.
Credential formats
| Cloud Provider | Credential Type | Format/Example | Use Case |
|---|---|---|---|
| AWS | Access Key | ini [default] aws_access_key_id=AKIA123... aws_secret_access_key=xyz123... | Used for AWS CLI, SDKs, and programmatic access. |
| AWS | IAM Role (Temporary Credentials) | json { "AccessKeyId": "ASIA123...", "SecretAccessKey": "xyz123...", "SessionToken": "FQoGZXIvYXdzE..." } | Temporary credentials via AssumeRole. |
| AWS | Environment Variables | sh export AWS_ACCESS_KEY_ID="AKIA123..." export AWS_SECRET_ACCESS_KEY="xyz123..." | Used in CI/CD pipelines, containers. |
| AWS | .env File | AWS_ACCESS_KEY_ID=AKIA123... AWS_SECRET_ACCESS_KEY=xyz123... | Stored in environment configuration files. |
| AWS | EC2 Instance Profile (Metadata API) | sh curl http://169.254.169.254/latest/meta-data/iam/security-credentials/ | IAM roles attached to EC2 instances. |
| Azure | Service Principal (JSON) | json { "clientId": "a2b3c4d5-e6f7...", "clientSecret": "P@ssw0rd123!", "subscriptionId": "12345678...", "tenantId": "abcdef12..." } | Used for automation, CLI, API access. |
| Azure | Storage Account Key | sh AZURE_STORAGE_ACCOUNT="mystorageaccount" AZURE_STORAGE_KEY="Eby8vdM02xNOcq..." | Access Azure Blob Storage. |
| Azure | Managed Identity | sh curl -H "Metadata: true" http://169.254.169.254/metadata/identity/oauth2/token | Secure way to authenticate without keys. |
| Azure | Environment Variables | sh export AZURE_CLIENT_ID="a2b3c4d5..." export AZURE_CLIENT_SECRET="P@ssw0rd123!" export AZURE_TENANT_ID="abcdef12..." | Used in automated deployments. |
| GCP | Service Account Key (JSON) | json { "type": "service_account", "project_id": "my-gcp-project", "private_key_id": "abcdef123...", "private_key": "-----BEGIN PRIVATE KEY-----\nMIIEvQ...", "client_email": "my-service-account@my-gcp-project.iam.gserviceaccount.com" } | Used for automation, authentication to GCP APIs. |
| GCP | OAuth2 Access Token | sh ACCESS_TOKEN="ya29.a0AfH6SMA..." | Temporary authentication for APIs. |
| GCP | API Key | sh GCP_API_KEY="AIzAxxxxxxxxxxxx" | Used in simple API requests. |
| GCP | Environment Variables | sh export GOOGLE_APPLICATION_CREDENTIALS="/path/to/service-account.json" | Common in GCP SDKs. |
| GCP | GKE Kubernetes Secret | yaml apiVersion: v1 kind: Secret metadata: name: gcp-credentials data: service_account.json: "BASE64_ENCODED_JSON" | Kubernetes authentication with GCP. |
| GCP | Compute Engine Metadata API | sh curl "http://metadata.google.internal/computeMetadata/v1/instance/service-accounts/default/token" -H "Metadata-Flavor: Google" | Retrieve tokens for service accounts on GCE instances. |
Table: APT Credential Theft Techniques in Cloud Environments
| Technique | Description | Example APT Groups | Mitigation Strategies |
|---|---|---|---|
| Phishing & Spear-Phishing | Crafting deceptive emails/messages to trick users into revealing credentials. | APT29 (Cozy Bear), APT40 | Security awareness training, MFA, email filtering |
| Password Spraying | Trying common passwords across multiple accounts to avoid detection. | APT29, APT35, APT41 | Enforce strong password policies, MFA, login anomaly detection |
| Brute-Force Attacks | Systematically attempting all possible password combinations. | APT33, Fancy Bear (APT28) | Rate-limiting login attempts, CAPTCHAs, MFA |
| Exploiting Third-Party Software | Targeting vulnerabilities in cloud-based applications and remote software. | APT10 (Cloud Hopper), Hafnium | Regular patching, vulnerability scanning, zero-trust architecture |
| Leveraging Dormant Accounts | Using inactive/unmonitored accounts to regain or maintain access. | APT29, Lazarus Group | Regular account audits, disabling inactive accounts, monitoring login anomalies |
| Using Cloud for C2 Infrastructure | Abusing trusted cloud services for command and control (C2) operations. | APT33, Mustang Panda | Anomalous network traffic monitoring, firewall rules, endpoint detection and response (EDR) |
| Credential Dumping | Extracting credentials from compromised systems using tools like Mimikatz. | APT28, APT35, FIN7 | Endpoint security solutions, LSASS protection, log monitoring |
| Man-in-the-Middle (MitM) Attacks | Intercepting traffic between users and cloud services to capture credentials. | Turla, APT41 | Enforce HTTPS/TLS, VPN encryption, DNS security |
| Default or Weak Credentials | Exploiting accounts using default or easily guessable passwords. | APT39, Sandworm | Enforce password policies, disable default credentials, MFA |
| Social Engineering & Impersonation | Manipulating individuals into revealing credentials by posing as trusted entities. | APT35 (Charming Kitten), APT37 | Security awareness training, phishing-resistant authentication |
| Session Hijacking | Taking over active user sessions to bypass authentication. | APT28, APT41 | Secure cookies, session timeout policies, endpoint protection |
| Exploiting OAuth & SSO Tokens | Using stolen OAuth tokens to bypass password-based authentication. | APT29, Nobelium | Token revocation policies, monitoring token usage, strict API permissions |
| Sniffing Network Traffic | Capturing unencrypted traffic to extract credentials. | Lazarus Group, FIN8 | TLS encryption, network segmentation, intrusion detection systems (IDS) |
| Exploiting Cloud API Keys | Gaining access through exposed API keys found in repositories or logs. | APT40, Hafnium | Rotate API keys regularly, use IAM roles instead of static keys, enforce environment variable security |
| Abusing IAM Policies & Privilege Escalation | Misconfiguring IAM policies to gain higher privileges. | APT10, APT39 | Principle of least privilege (PoLP), regular IAM reviews, enforcing role-based access control (RBAC) |
After Obtaining Initial Credentials
While various methodologies exist, a top-down approach is often the most structured. Azure’s Tenant → Subscription → Service model is particularly clear and organized:
- Tenant: Identifies the entity (e.g., company).
- Subscription: Linked to a tenant, responsible for billing and resource allocation.
- Services: Compute, Storage, Networking, Databases, etc.
Comparison of Cloud Hierarchies
| Cloud Provider | Level 1 (Tenant) | Level 2 (Subscription) | Level 3 (Services) |
|---|---|---|---|
| Azure | Tenant (Microsoft Entra ID) | Subscription (Billing & Resource Container) | Services (VMs, Storage, Databases, etc.) |
| AWS | AWS Organization (Root Account) | Account (Isolated Unit for Billing & Resources) | Services (EC2, S3, RDS, etc.) |
| GCP | Organization (Root Entity) | Project (Billing & Resource Container) | Services (Compute Engine, Cloud Storage, BigQuery, etc.) |
Mermaid Diagram for Cloud Hierarchies
graph TD;
A[Azure Tenant] --> B[Azure Subscription] --> C[Azure Services];
D[AWS Organization] --> E[AWS Account] --> F[AWS Services];
G[GCP Organization] --> H[GCP Project] --> I[GCP Services];Tools and Techniques for Cloud Pentesting
While specific tools vary across cloud providers, the core techniques remain the same:
- Enumerating services
- Identifying misconfigurations
- Exploiting vulnerabilities
**Cloud Pentesting Workflow **
graph TD;
A[Start] --> B[Verify supplied lab identity and scope];
B --> C[Enumerate Users] --> F[Access Environment];
B --> D[Inspect seeded canary exposure] --> F;
B --> E[Validate one approved control] --> F;
F --> G[Map authorized hierarchy] --> H[List approved services] --> I[Find control gaps] --> J[Stop at benign proof] --> K[Restore and report] --> L[End];