AWS Password Policy Password Age Limit

AnalysisType: policy
Filename: aws_password_policy_password_age_limit.py
PolicyID: "AWS.PasswordPolicy.PasswordAgeLimit"
DisplayName: "AWS Password Policy Password Age Limit"
Enabled: true
ResourceTypes:
  - AWS.PasswordPolicy
Tags:
  - AWS
  - Identity & Access Management
  - Credential Access:Brute Force
Reports:
  CIS:
    - 1.11
  PCI:
    - 8.2.4
  MITRE ATT&CK:
    - TA0006:T1110
Severity: Medium
Description: >
  This policy validates that the account password policy enforces a maximum password age of 90
  days or less.
Runbook: >
  https://docs.runpanther.io/alert-runbooks/built-in-policies/aws-account-password-policy-enforces-password-age-limit-of-90-days-or-less
Reference: https://docs.aws.amazon.com/IAM/latest/UserGuide/best-practices.html
Tests:
  - Name: Adequate Max Password Age Set
    ExpectedResult: true
    Resource:
      {
        "AllowUsersToChangePassword": false,
        "AnyExist": true,
        "ExpirePasswords": true,
        "HardExpiry": false,
        "MaxPasswordAge": 75,
        "MinimumPasswordLength": 14,
        "PasswordReusePrevention": 24,
        "RequireLowercaseCharacters": true,
        "RequireNumbers": true,
        "RequireSymbols": true,
        "RequireUppercaseCharacters": true,
      }
  - Name: Inadequate Max Password Age Set
    ExpectedResult: false
    Resource:
      {
        "AllowUsersToChangePassword": false,
        "AnyExist": true,
        "ExpirePasswords": true,
        "HardExpiry": false,
        "MaxPasswordAge": 180,
        "MinimumPasswordLength": 14,
        "PasswordReusePrevention": 24,
        "RequireLowercaseCharacters": true,
        "RequireNumbers": true,
        "RequireSymbols": true,
        "RequireUppercaseCharacters": true,
      }
  - Name: Max Password Age Not Set
    ExpectedResult: false
    Resource:
      {
        "AllowUsersToChangePassword": false,
        "AnyExist": true,
        "ExpirePasswords": true,
        "HardExpiry": false,
        "MaxPasswordAge": null,
        "MinimumPasswordLength": 14,
        "PasswordReusePrevention": 24,
        "RequireLowercaseCharacters": true,
        "RequireNumbers": true,
        "RequireSymbols": true,
        "RequireUppercaseCharacters": true,
      }


# ------ paired body: aws_password_policy_password_age_limit.py ------

def policy(resource):
    if resource["MaxPasswordAge"] is None:
        return False
    return resource["MaxPasswordAge"] <= 90