aws-iam-best-practices

---
name: aws-iam-best-practices
description: "AWS IAM Best Practices workflow skill. Use this skill when the user needs IAM policy review, hardening, and least privilege implementation and the operator should preserve the upstream workflow, copied support files, and provenance before merging or handing off."
version: "0.0.1"
category: testing-security
tags: ["aws", "iam", "security", "access-control", "kiro-cli", "least-privilege", "aws-iam-best-practices", "policy"]
complexity: advanced
risk: caution
tools: ["codex-cli", "claude-code", "cursor", "gemini-cli", "opencode"]
source: community
author: "sickn33"
date_added: "2026-04-15"
date_updated: "2026-04-25"
---

# AWS IAM Best Practices

## Overview

This public intake copy packages `plugins/antigravity-awesome-skills-claude/skills/security/aws-iam-best-practices` from `https://github.com/sickn33/antigravity-awesome-skills` into the native Omni Skills editorial shape without hiding its origin.

Use it when the operator needs the upstream workflow, support files, and repository context to stay intact while the public validator and private enhancer continue their normal downstream flow.

This intake keeps the copied upstream files intact and uses the `external_source` block in `metadata.json` plus `ORIGIN.md` as the provenance anchor for review.

# AWS IAM Best Practices Review and harden IAM policies following AWS security best practices and least privilege principles.

Imported source sections that did not map cleanly to the public headings are still preserved below or in the support files. Notable imported sections: IAM Security Checks, IAM Hardening Checklist, Automated IAM Hardening, Kiro CLI Integration, Limitations.

## When to Use This Skill

Use this section as the trigger filter. It should make the activation boundary explicit before the operator loads files, runs commands, or opens a pull request.

- Use this skill when you need to review IAM policies, implement least privilege access, or harden IAM security.
- Use when the request clearly matches the imported source intent: IAM policy review, hardening, and least privilege implementation.
- Use when the operator should preserve upstream workflow detail instead of rewriting the process from scratch.
- Use when provenance needs to stay visible in the answer, PR, or review packet.
- Use when copied upstream references, examples, or scripts materially improve the answer.
- Use when the workflow should remain reviewable in the public intake repo before the private enhancer takes over.

## Operating Table

| Situation | Start here | Why it matters |
| --- | --- | --- |
| First-time use | `metadata.json` | Confirms repository, branch, commit, and imported path through the `external_source` block before touching the copied workflow |
| Provenance review | `ORIGIN.md` | Gives reviewers a plain-language audit trail for the imported source |
| Workflow execution | `SKILL.md` | Starts with the smallest copied file that materially changes execution |
| Supporting context | `SKILL.md` | Adds the next most relevant copied source file without loading the entire package |
| Handoff decision | `## Related Skills` | Helps the operator switch to a stronger native skill when the task drifts |

## Workflow

This workflow is intentionally editorial and operational at the same time. It keeps the imported source useful to the operator while still satisfying the public intake standards that feed the downstream enhancer flow.

1. Confirm the user goal, the scope of the imported workflow, and whether this skill is still the right router for the task.
2. Read the overview and provenance files before loading any copied upstream support files.
3. Load only the references, examples, prompts, or scripts that materially change the outcome for the current request.
4. Execute the upstream workflow while keeping provenance and source boundaries explicit in the working notes.
5. Validate the result against the upstream expectations and the evidence you can point to in the copied files.
6. Escalate or hand off to a related skill when the work moves out of this imported workflow's center of gravity.
7. Before merge or closure, record what was used, what changed, and what the reviewer still needs to verify.

### Imported Workflow Notes

#### Imported: IAM Security Checks

### Find Overly Permissive Policies

```bash
# List policies with full admin access
aws iam list-policies --scope Local \
  --query 'Policies[*].[PolicyName,Arn]' --output table | \
  grep -i admin

# Find policies with wildcard actions
aws iam list-policies --scope Local --query 'Policies[*].Arn' --output text | \
while read arn; do
  version=$(aws iam get-policy --policy-arn "$arn" \
    --query 'Policy.DefaultVersionId' --output text)
  doc=$(aws iam get-policy-version --policy-arn "$arn" \
    --version-id "$version" --query 'PolicyVersion.Document')
  if echo "$doc" | grep -q '"Action": "\*"'; then
    echo "Wildcard action in: $arn"
  fi
done

# Find inline policies (should use managed policies)
aws iam list-users --query 'Users[*].UserName' --output text | \
while read user; do
  policies=$(aws iam list-user-policies --user-name "$user" \
    --query 'PolicyNames' --output text)
  if [ -n "$policies" ]; then
    echo "Inline policies on user $user: $policies"
  fi
done
```

### MFA Enforcement

```bash
# List users without MFA
aws iam get-credential-report --output text | \
  awk -F, 'NR>1 && $4=="false" {print $1}'

# Check if MFA is required in policies
aws iam list-policies --scope Local --query 'Policies[*].Arn' --output text | \
while read arn; do
  version=$(aws iam get-policy --policy-arn "$arn" \
    --query 'Policy.DefaultVersionId' --output text)
  doc=$(aws iam get-policy-version --policy-arn "$arn" \
    --version-id "$version" --query 'PolicyVersion.Document')
  if echo "$doc" | grep -q "aws:MultiFactorAuthPresent"; then
    echo "MFA enforced in: $arn"
  fi
done

# Enable MFA for a user (returns QR code)
aws iam create-virtual-mfa-device \
  --virtual-mfa-device-name user-mfa \
  --outfile /tmp/qr.png \
  --bootstrap-method QRCodePNG
```

### Access Key Management

```bash
# Find old access keys (>90 days)
aws iam list-users --query 'Users[*].UserName' --output text | \
while read user; do
  aws iam list-access-keys --user-name "$user" \
    --query 'AccessKeyMetadata[*].[AccessKeyId,CreateDate,Status]' \
    --output text | \
  while read key_id create_date status; do
    age_days=$(( ($(date +%s) - $(date -d "$create_date" +%s)) / 86400 ))
    if [ $age_days -gt 90 ]; then
      echo "$user: Key $key_id is $age_days days old"
    fi
  done
done

# Rotate access key
OLD_KEY="AKIAIOSFODNN7EXAMPLE"
USER="myuser"

# Create new key
NEW_KEY=$(aws iam create-access-key --user-name "$USER")
echo "New key created. Update applications, then run:"
echo "aws iam delete-access-key --user-name $USER --access-key-id $OLD_KEY"

# Deactivate old key (test first)
aws iam update-access-key \
  --user-name "$USER" \
  --access-key-id "$OLD_KEY" \
  --status Inactive
```

### Role and Policy Analysis

```bash
# List unused roles (no activity in 90 days)
aws iam list-roles --query 'Roles[*].[RoleName,RoleLastUsed.LastUsedDate]' \
  --output text | \
while read role last_used; do
  if [ "$last_used" = "None" ]; then
    echo "Never used: $role"
  fi
done

# Find roles with trust relationships to external accounts
aws iam list-roles --query 'Roles[*].RoleName' --output text | \
while read role; do
  trust=$(aws iam get-role --role-name "$role" \
    --query 'Role.AssumeRolePolicyDocument')
  if echo "$trust" | grep -q '"AWS":'; then
    echo "External trust: $role"
  fi
done

# Analyze policy permissions
aws iam simulate-principal-policy \
  --policy-source-arn arn:aws:iam::123456789012:user/myuser \
  --action-names s3:GetObject s3:PutObject \
  --resource-arns arn:aws:s3:::mybucket/*
```

## Examples

### Example 1: Ask for the upstream workflow directly

```text
Use @aws-iam-best-practices to handle <task>. Start from the copied upstream workflow, load only the files that change the outcome, and keep provenance visible in the answer.
```

**Explanation:** This is the safest starting point when the operator needs the imported workflow, but not the entire repository.

### Example 2: Ask for a provenance-grounded review

```text
Review @aws-iam-best-practices against metadata.json and ORIGIN.md, then explain which copied upstream files you would load first and why.
```

**Explanation:** Use this before review or troubleshooting when you need a precise, auditable explanation of origin and file selection.

### Example 3: Narrow the copied support files before execution

```text
Use @aws-iam-best-practices for <task>. Load only the copied references, examples, or scripts that change the outcome, and name the files explicitly before proceeding.
```

**Explanation:** This keeps the skill aligned with progressive disclosure instead of loading the whole copied package by default.

### Example 4: Build a reviewer packet

```text
Review @aws-iam-best-practices using the copied upstream files plus provenance, then summarize any gaps before merge.
```

**Explanation:** This is useful when the PR is waiting for human review and you want a repeatable audit packet.

### Imported Usage Notes

#### Imported: Example Prompts

- "Review my IAM policies for security issues"
- "Find users without MFA enabled"
- "Create a least privilege policy for S3 access"
- "Identify overly permissive IAM roles"
- "Generate an IAM hardening report"

## Best Practices

Treat the generated public skill as a reviewable packaging layer around the upstream repository. The goal is to keep provenance explicit and load only the copied source material that materially improves execution.

- Grant minimum permissions needed
- Use managed policies when possible
- Avoid wildcard (*) permissions
- Regular access reviews
- Enable MFA for all users
- Use IAM roles instead of access keys
- Implement service control policies (SCPs)

### Imported Operating Notes

#### Imported: Core Principles

**Least Privilege**
- Grant minimum permissions needed
- Use managed policies when possible
- Avoid wildcard (*) permissions
- Regular access reviews

**Defense in Depth**
- Enable MFA for all users
- Use IAM roles instead of access keys
- Implement service control policies (SCPs)
- Enable CloudTrail for audit

**Separation of Duties**
- Separate admin and user roles
- Use different roles for different environments
- Implement approval workflows
- Regular permission audits

#### Imported: IAM Policy Templates

### Least Privilege S3 Access

```json
{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "s3:GetObject",
        "s3:PutObject"
      ],
      "Resource": "arn:aws:s3:::my-bucket/user-data/${aws:username}/*"
    },
    {
      "Effect": "Allow",
      "Action": "s3:ListBucket",
      "Resource": "arn:aws:s3:::my-bucket",
      "Condition": {
        "StringLike": {
          "s3:prefix": "user-data/${aws:username}/*"
        }
      }
    }
  ]
}
```

### MFA-Required Policy

```json
{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Deny",
      "Action": "*",
      "Resource": "*",
      "Condition": {
        "BoolIfExists": {
          "aws:MultiFactorAuthPresent": "false"
        }
      }
    }
  ]
}
```

### Time-Based Access

```json
{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": "ec2:*",
      "Resource": "*",
      "Condition": {
        "DateGreaterThan": {
          "aws:CurrentTime": "2026-01-01T00:00:00Z"
        },
        "DateLessThan": {
          "aws:CurrentTime": "2026-12-31T23:59:59Z"
        }
      }
    }
  ]
}
```

### IP-Restricted Access

```json
{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Deny",
      "Action": "*",
      "Resource": "*",
      "Condition": {
        "NotIpAddress": {
          "aws:SourceIp": [
            "203.0.113.0/24",
            "198.51.100.0/24"
          ]
        }
      }
    }
  ]
}
```

#### Imported: Best Practices

- Use AWS managed policies when possible
- Implement policy versioning
- Test policies in non-production first
- Document policy purposes
- Regular access reviews (quarterly)
- Use IAM Access Analyzer
- Implement SCPs for organization-wide controls

## Troubleshooting

### Problem: The operator skipped the imported context and answered too generically

**Symptoms:** The result ignores the upstream workflow in `plugins/antigravity-awesome-skills-claude/skills/security/aws-iam-best-practices`, fails to mention provenance, or does not use any copied source files at all.
**Solution:** Re-open `metadata.json`, `ORIGIN.md`, and the most relevant copied upstream files. Check the `external_source` block first, then restate the provenance before continuing.

### Problem: The imported workflow feels incomplete during review

**Symptoms:** Reviewers can see the generated `SKILL.md`, but they cannot quickly tell which references, examples, or scripts matter for the current task.
**Solution:** Point at the exact copied references, examples, scripts, or assets that justify the path you took. If the gap is still real, record it in the PR instead of hiding it.

### Problem: The task drifted into a different specialization

**Symptoms:** The imported skill starts in the right place, but the work turns into debugging, architecture, design, security, or release orchestration that a native skill handles better.
**Solution:** Use the related skills section to hand off deliberately. Keep the imported provenance visible so the next skill inherits the right context instead of starting blind.



## Related Skills

- `@00-andruia-consultant` - Use when the work is better handled by that native specialization after this imported skill establishes context.
- `@00-andruia-consultant-v2` - Use when the work is better handled by that native specialization after this imported skill establishes context.
- `@10-andruia-skill-smith` - Use when the work is better handled by that native specialization after this imported skill establishes context.
- `@10-andruia-skill-smith-v2` - Use when the work is better handled by that native specialization after this imported skill establishes context.

## Additional Resources

Use this support matrix and the linked files below as the operator packet for this imported skill. They should reflect real copied source material, not generic scaffolding.

| Resource family | What it gives the reviewer | Example path |
| --- | --- | --- |
| `references` | copied reference notes, guides, or background material from upstream | `references/n/a` |
| `examples` | worked examples or reusable prompts copied from upstream | `examples/n/a` |
| `scripts` | upstream helper scripts that change execution or validation | `scripts/n/a` |
| `agents` | routing or delegation notes that are genuinely part of the imported package | `agents/n/a` |
| `assets` | supporting assets or schemas copied from the source package | `assets/n/a` |



### Imported Reference Notes

#### Imported: Additional Resources

- [IAM Best Practices](https://docs.aws.amazon.com/IAM/latest/UserGuide/best-practices.html)
- [IAM Policy Simulator](https://policysim.aws.amazon.com/)
- [IAM Access Analyzer](https://aws.amazon.com/iam/features/analyze-access/)

#### Imported: IAM Hardening Checklist

**User Management**
- [ ] Enable MFA for all users
- [ ] Remove unused IAM users
- [ ] Rotate access keys every 90 days
- [ ] Use IAM roles instead of long-term credentials
- [ ] Implement password policy (length, complexity, rotation)

**Policy Management**
- [ ] Replace inline policies with managed policies
- [ ] Remove wildcard (*) permissions
- [ ] Implement least privilege
- [ ] Use policy conditions (MFA, IP, time)
- [ ] Regular policy reviews

**Role Management**
- [ ] Use roles for EC2 instances
- [ ] Implement cross-account roles properly
- [ ] Review trust relationships
- [ ] Remove unused roles
- [ ] Use session tags for fine-grained access

**Monitoring**
- [ ] Enable CloudTrail for IAM events
- [ ] Set up CloudWatch alarms for IAM changes
- [ ] Use AWS IAM Access Analyzer
- [ ] Regular access reviews
- [ ] Monitor for privilege escalation

#### Imported: Automated IAM Hardening

```python
#!/usr/bin/env python3
# iam-hardening.py

import boto3
from datetime import datetime, timedelta

iam = boto3.client('iam')

def enforce_mfa():
    """Identify users without MFA"""
    users = iam.list_users()['Users']
    no_mfa = []

    for user in users:
        mfa_devices = iam.list_mfa_devices(
            UserName=user['UserName']
        )['MFADevices']

        if not mfa_devices:
            no_mfa.append(user['UserName'])

    return no_mfa

def rotate_old_keys():
    """Find access keys older than 90 days"""
    users = iam.list_users()['Users']
    old_keys = []

    for user in users:
        keys = iam.list_access_keys(
            UserName=user['UserName']
        )['AccessKeyMetadata']

        for key in keys:
            age = datetime.now(key['CreateDate'].tzinfo) - key['CreateDate']
            if age.days > 90:
                old_keys.append({
                    'user': user['UserName'],
                    'key_id': key['AccessKeyId'],
                    'age_days': age.days
                })

    return old_keys

def find_overpermissive_policies():
    """Find policies with wildcard actions"""
    policies = iam.list_policies(Scope='Local')['Policies']
    overpermissive = []

    for policy in policies:
        version = iam.get_policy_version(
            PolicyArn=policy['Arn'],
            VersionId=policy['DefaultVersionId']
        )

        doc = version['PolicyVersion']['Document']
        for statement in doc.get('Statement', []):
            if statement.get('Action') == '*':
                overpermissive.append(policy['PolicyName'])
                break

    return overpermissive

if __name__ == "__main__":
    print("IAM Hardening Report")
    print("=" * 50)

    print("\nUsers without MFA:")
    for user in enforce_mfa():
        print(f"  - {user}")

    print("\nOld access keys (>90 days):")
    for key in rotate_old_keys():
        print(f"  - {key['user']}: {key['age_days']} days")

    print("\nOverpermissive policies:")
    for policy in find_overpermissive_policies():
        print(f"  - {policy}")
```

#### Imported: Kiro CLI Integration

```bash
kiro-cli chat "Use aws-iam-best-practices to review my IAM setup"
kiro-cli chat "Create a least privilege policy with aws-iam-best-practices"
```

#### Imported: Limitations

- Use this skill only when the task clearly matches the scope described above.
- Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
- Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.