GCP Terraform Misconfiguration: Compute Engine Project-Wide SSH

Abstract

Terraform 組態設定了一個 Compute Engine 執行個體，而不封鎖專案層級 SSH 登入。

Explanation

依預設，您可以使用儲存在專案中繼資料中的 SSH 金鑰，來存取專案中的所有 Compute Engine 執行個體。這不僅會大幅擴大任何遭入侵 SSH 金鑰可存取的受攻擊面，同時也違反最小權限原則。

範例 1：以下範例顯示一個 Terraform 組態，其透過將 metadata 引數中的 block-project-ssh-keys 設定為 false 來允許專案層級 SSH 登入。


resource "google_compute_instance" "compute_instance_demo" {
  ...
  metadata = {
    block-project-ssh-keys = false
    ...
  }
  ...
}

References

[1] HashiCorp google_compute_instance

[2] Google Cloud Restrict SSH keys from VMs

[3] Standards Mapping - CIS Google Cloud Computing Platform Benchmark Recommendation 4.3

[4] Standards Mapping - Common Weakness Enumeration CWE ID 250

[5] Standards Mapping - Common Weakness Enumeration Top 25 2024 [15] CWE ID 269

[6] Standards Mapping - DISA Control Correlation Identifier Version 2 CCI-000381, CCI-002233, CCI-002235

[7] Standards Mapping - FIPS200 AC

[8] Standards Mapping - General Data Protection Regulation (GDPR) Access Violation

[9] Standards Mapping - NIST Special Publication 800-53 Revision 4 AC-6 Least Privilege (P1), CM-7 Least Functionality (P1)

[10] Standards Mapping - NIST Special Publication 800-53 Revision 5 AC-6 Least Privilege, CM-7 Least Functionality

[11] Standards Mapping - OWASP API 2023 API8 Security Misconfiguration

[12] Standards Mapping - OWASP Application Security Verification Standard 4.0 4.1.3 General Access Control Design (L1 L2 L3), 4.1.4 General Access Control Design (L1 L2 L3)

[13] Standards Mapping - OWASP Top 10 2017 A5 Broken Access Control

[14] Standards Mapping - OWASP Top 10 2021 A01 Broken Access Control

[15] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2.1 Requirement 7.1.2

[16] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0 Requirement 7.2.2

[17] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0.1 Requirement 7.2.2

[18] Standards Mapping - Payment Card Industry Software Security Framework 1.0 Control Objective 5.4 - Authentication and Access Control

[19] Standards Mapping - Payment Card Industry Software Security Framework 1.1 Control Objective 5.4 - Authentication and Access Control

[20] Standards Mapping - Payment Card Industry Software Security Framework 1.2 Control Objective 5.4 - Authentication and Access Control, Control Objective C.2.3 - Web Software Access Controls

[21] Standards Mapping - Security Technical Implementation Guide Version 4.11 APSC-DV-000500 CAT II, APSC-DV-000510 CAT I, APSC-DV-001500 CAT II

[22] Standards Mapping - Security Technical Implementation Guide Version 5.1 APSC-DV-000500 CAT II, APSC-DV-000510 CAT I, APSC-DV-001500 CAT II

[23] Standards Mapping - Security Technical Implementation Guide Version 5.2 APSC-DV-000500 CAT II, APSC-DV-000510 CAT I, APSC-DV-001500 CAT II

[24] Standards Mapping - Security Technical Implementation Guide Version 5.3 APSC-DV-000500 CAT II, APSC-DV-000510 CAT I, APSC-DV-001500 CAT II

[25] Standards Mapping - Security Technical Implementation Guide Version 6.1 APSC-DV-000500 CAT II, APSC-DV-000510 CAT I, APSC-DV-001500 CAT II

[26] Standards Mapping - Security Technical Implementation Guide Version 6.2 APSC-DV-000500 CAT II, APSC-DV-000510 CAT I, APSC-DV-001500 CAT II

desc.structural.hcl.gcp_terraform_misconfiguration_compute_engine_project_wide_ssh