[Hardening] F-12: Absence of Per-Account or Per-User Source CIDR Allowlist.

### The required feature described as a wish

**Description:** CloudStack does not provide a built-in mechanism to restrict per-account or per-user access to a defined set of source IP addresses or CIDR ranges. Any IP address that can reach the management plane can attempt to authenticate as any account.

**Affected Components:** Management UI / API

**Impact:** Without source IP allowlisting, a stolen API key or compromised credential set can be used from any network location globally. There is no network-level control to limit the blast radius of a credential compromise. High-privilege service accounts are particularly at risk, as they can be accessed from unexpected locations without raising any flags.

**Steps to Reproduce:**
- This finding is not directly reproducible since it reflects the absence of a control.

**Recommended Remediation:** Implement a per-account or per-user source CIDR allowlist field in the data model. Requests originating from IPs outside the defined allowlist should be rejected and logged as a security event.

A issue identifica a Management UI/API, o modelo de dados da conta ou do usuário, as verificações do IP de origem das requisições e o registro de Security-Events, mas não indica arquivos nem testes. Comece localizando esses pontos de entrada e rastreando a autenticação e a autorização das requisições à API. A conclusão deve incluir uma política CIDR definida por conta ou por usuário, a rejeição fora da política e Security-Events registrados, com cobertura do comportamento relevante.

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