IAM Policies With Full Privileges

• Query id: 953b3cdb-ce13-428a-aa12-318726506661
• Query name: IAM Policies With Full Privileges
• Platform: CloudFormation
• Severity: Medium
• Category: Access Control
• URL: Github

Description

IAM policies shouldn't allow full administrative privileges (for all resources)
Documentation

Code samples

Code samples with security vulnerabilities

Positive test num. 1 - yaml file

AWSTemplateFormatVersion: "2010-09-09"
Description: A sample template
Resources:
  mypolicy:
    Type: AWS::IAM::Policy
    Properties:
      PolicyName: mygrouppolicy
      PolicyDocument:
        Version: '2012-10-17'
        Statement:
        - Effect: Allow
          Action: ["*"]
          Resource: "*"
      Groups:
      - myexistinggroup1
      - !Ref mygroup
  mypolicy2:
    Type: AWS::IAM::Policy
    Properties:
      PolicyName: mygrouppolicy
      PolicyDocument:
        Version: '2012-10-17'
        Statement:
        - Effect: Allow
          Action: "*"
          Resource: "*"
      Groups:
      - myexistinggroup1
      - !Ref mygroup

Positive test num. 2 - json file

{
  "AWSTemplateFormatVersion": "2010-09-09",
  "Description": "A sample template",
  "Resources": {
    "mypolicy": {
      "Type": "AWS::IAM::Policy",
      "Properties": {
        "PolicyName": "mygrouppolicy",
        "PolicyDocument": {
          "Version": "2012-10-17",
          "Statement": [
            {
              "Effect": "Allow",
              "Action": [
                "*"
              ],
              "Resource": "*"
            }
          ]
        },
        "Groups": [
          "myexistinggroup1",
          "mygroup"
        ]
      }
    },
    "mypolicy2": {
      "Type": "AWS::IAM::Policy",
      "Properties": {
        "PolicyName": "mygrouppolicy",
        "PolicyDocument": {
          "Version": "2012-10-17",
          "Statement": [
            {
              "Effect": "Allow",
              "Action": "*",
              "Resource": "*"
            }
          ]
        },
        "Groups": [
          "myexistinggroup1",
          "mygroup"
        ]
      }
    }
  }
}

Code samples without security vulnerabilities

Negative test num. 1 - yaml file

AWSTemplateFormatVersion: "2010-09-09"
Description: A sample template
Resources:
  MyPolicy:
    Type: AWS::IAM::Policy
    Properties:
      PolicyName: mygrouppolicy
      PolicyDocument:
        Version: "2012-10-17"
        Statement:
          - Effect: Allow
            Action:
              - s3:GetObject
              - s3:PutObject
              - s3:PutObjectAcl
            Resource: arn:aws:s3:::myAWSBucket/*
      Groups:
        - myexistinggroup1
        - !Ref mygroup

Negative test num. 2 - json file

{
  "AWSTemplateFormatVersion": "2010-09-09",
  "Description": "A sample template",
  "Resources": {
    "MyPolicy": {
      "Properties": {
        "PolicyName": "mygrouppolicy",
        "PolicyDocument": {
          "Version": "2012-10-17",
          "Statement": [
            {
              "Effect": "Allow",
              "Action": [
                "s3:GetObject",
                "s3:PutObject",
                "s3:PutObjectAcl"
              ],
              "Resource": "arn:aws:s3:::myAWSBucket/*"
            }
          ]
        },
        "Groups": [
          "myexistinggroup1",
          "mygroup"
        ]
      },
      "Type": "AWS::IAM::Policy"
    }
  }
}