mcp-server-semgrep/semgrep-rules/terraform/lang/security/iam/no-iam-star-actions.yaml

MCP Server for Semgrep Integration - static code analysis with AI

rules:
- id: no-iam-star-actions
  patterns:
  - pattern-either:
    - patterns:
      - pattern-inside: |
          resource $TYPE "..." {
            ...
            policy = jsonencode({
              ...
              Statement = [
                ...
              ]
              ...
            })
            ...
          }
      - pattern-not-inside: |
          resource $TYPE "..." {
            ...
            policy = jsonencode({
              ...
              Statement = [
                ...,
                {... Effect = "Deny" ...},
                ...
              ]
              ...
            })
            ...
          }
      - pattern-either:
        - pattern: Action = "*"
        - pattern: 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 {
              ...
            }
            ...
          }
      - pattern-not-inside: |
          data aws_iam_policy_document "..." {
            ...
            statement {
              ...
              effect = "Deny"
              ...
            }
            ...
          }
      - pattern: |
          actions = ["*"]
  message: >-
    Ensure that no IAM policies allow "*" as a statement's actions. This allows all actions
    to be performed on the specified resources, and is a violation of the principle of least privilege.
    Instead, specify the actions that a certain user or policy is allowed to take.
  metadata:
    references:
    - https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/iam_policy
    - https://github.com/bridgecrewio/checkov/blob/ca830e14745c2c8e1b941985f305abe985d7f1f9/checkov/terraform/checks/data/aws/StarActionPolicyDocument.py
    category: security
    cwe:
    - 'CWE-269: Improper Privilege Management'
    technology:
    - terraform
    - aws
    owasp:
    - A04:2021 - Insecure Design
    subcategory:
    - audit
    likelihood: LOW
    impact: LOW
    confidence: LOW
  languages: [hcl]
  severity: WARNING