mcp-server-semgrep/semgrep-rules/terraform/lang/security/iam/no-iam-data-exfiltration.yaml

MCP Server for Semgrep Integration - static code analysis with AI

rules:
- id: no-iam-data-exfiltration
  patterns:
  - pattern-either:
    - patterns:
      - pattern-inside: |
          resource $TYPE "..." {
            ...
            policy = jsonencode({
              ...
              Statement = [
                ...,
                {... Resource = "*" ...},
                ...
              ]
              ...
            })
            ...
          }
      - pattern-not-inside: |
          resource $TYPE "..." {
            ...
            policy = jsonencode({
              ...
              Statement = [
                ...,
                {... Effect = "Deny" ...},
                ...
              ]
              ...
            })
            ...
          }
      - pattern: |
          Action = $ACTION
      - metavariable-pattern:
          metavariable: $TYPE
          pattern-either:
          - pattern: |
              "aws_iam_role_policy"
          - pattern: |
              "aws_iam_policy"
          - pattern: |
              "aws_iam_user_policy"
          - pattern: |
              "aws_iam_group_policy"
    - patterns:
      - pattern-inside: |
          data aws_iam_policy_document "..." {
            ...
            statement {
              ...
              resources = ["*"]
              ...
            }
            ...
          }
      - pattern-not-inside: |
          data aws_iam_policy_document "..." {
            ...
            statement {
              ...
              effect = "Deny"
              ...
            }
            ...
          }
      - pattern: |
          actions = [..., $ACTION, ...]
  - metavariable-pattern:
      metavariable: $ACTION
      pattern-either:
      - pattern: |
          "s3:GetObject"
      - pattern: |
          "ssm:GetParameter*"
      - pattern: |
          "secretsmanager:GetSecretValue"
      - pattern: |
          "rds:CopyDBSnapshot"
      - pattern: |
          "rds:CreateDBSnapshot"
      - pattern: |
          "ssm:*"
      - pattern: |
          "s3:*"
      - pattern: |
          "rds:*"
      - pattern: |
          "rn: secretsmanager:*"
  message: >-
    Ensure that IAM policies don't allow data exfiltration actions that are not resource-constrained.
    This can allow the user to read sensitive data they don't need to read.
    Instead, make sure that the user granted these privileges are given these permissions on specific
    resources.
  metadata:
    references:
    - https://github.com/bridgecrewio/checkov/blob/ca830e14745c2c8e1b941985f305abe985d7f1f9/checkov/terraform/checks/data/aws/IAMDataExfiltration.py
    - https://cloudsplaining.readthedocs.io/en/latest/glossary/data-exfiltration/
    category: security
    cwe:
    - 'CWE-200: Exposure of Sensitive Information to an Unauthorized Actor'
    technology:
    - terraform
    - aws
    owasp:
    - A01:2021 - Broken Access Control
    cwe2021-top25: true
    subcategory:
    - audit
    likelihood: LOW
    impact: LOW
    confidence: LOW
  languages: [hcl]
  severity: WARNING