Performing AWS Privilege Escalation Assessment

When to Use

• When conducting authorized penetration testing of AWS IAM configurations
• When validating that IAM policies follow the principle of least privilege
• When assessing the blast radius of a compromised AWS credential
• When building security reviews for IAM role and policy changes in CI/CD pipelines
• When evaluating cross-account trust relationships for privilege escalation risks

Do not use for unauthorized testing against AWS accounts, for assessing non-IAM attack vectors (SSRF, application vulnerabilities), or as a substitute for comprehensive cloud penetration testing. Always obtain written authorization before testing.

Prerequisites

• Written authorization for privilege escalation testing in the target AWS account
• Test IAM user or role with limited permissions as the starting point
• Pacu installed (pip install pacu)
• CloudFox installed (go install github.com/BishopFox/cloudfox@latest)
• PMapper (Principal Mapper) installed (pip install principalmapper)
• AWS CLI configured with test credentials and CloudTrail logging enabled for audit trail

Workflow

Step 1: Enumerate Starting Permissions

Establish the baseline permissions of the test principal before attempting escalation.

# Get current identity
aws sts get-caller-identity

# Enumerate inline and attached policies for the current user
aws iam list-user-policies --user-name test-user
aws iam list-attached-user-policies --user-name test-user

# Get group memberships and group policies
aws iam list-groups-for-user --user-name test-user
for group in $(aws iam list-groups-for-user --user-name test-user --query 'Groups[*].GroupName' --output text); do
  echo "=== Group: $group ==="
  aws iam list-group-policies --group-name "$group"
  aws iam list-attached-group-policies --group-name "$group"
done

# Simulate specific API calls to map effective permissions
aws iam simulate-principal-policy \
  --policy-source-arn arn:aws:iam::ACCOUNT:user/test-user \
  --action-names iam:CreateUser iam:AttachUserPolicy iam:PassRole \
    lambda:CreateFunction ec2:RunInstances sts:AssumeRole \
  --query 'EvaluationResults[*].[EvalActionName,EvalDecision]' --output table

Step 2: Scan for Privilege Escalation Paths with Pacu

Use Pacu's privilege escalation scanner to identify known IAM escalation techniques.

# Start Pacu session
pacu

# Create session and set credentials
Pacu (new:session) > set_keys --key-alias privesc-test

# Enumerate IAM configuration
Pacu > run iam__enum_users_roles_policies_groups
Pacu > run iam__enum_permissions

# Run privilege escalation scanner
Pacu > run iam__privesc_scan

# The scanner checks for 21+ known escalation methods including:
# - iam:CreatePolicyVersion (create admin policy version)
# - iam:SetDefaultPolicyVersion (revert to permissive older version)
# - iam:AttachUserPolicy / iam:AttachRolePolicy (attach admin policy)
# - iam:PutUserPolicy / iam:PutRolePolicy (create inline admin policy)
# - iam:PassRole + lambda:CreateFunction (Lambda with admin role)
# - iam:PassRole + ec2:RunInstances (EC2 with admin instance profile)
# - iam:CreateLoginProfile / iam:UpdateLoginProfile (set console password)
# - iam:CreateAccessKey (create keys for other users)
# - sts:AssumeRole (assume more privileged roles)
# - glue:CreateDevEndpoint + iam:PassRole (Glue with admin role)

Step 3: Map Privilege Escalation Graphs with PMapper

Use Principal Mapper to build a graph of all IAM principals and identify escalation edges.

# Collect IAM data for graph construction
pmapper graph create --account ACCOUNT_ID

# Query for paths to admin
pmapper query 'who can do iam:AttachUserPolicy with * on *'
pmapper query 'who can do sts:AssumeRole with arn:aws:iam::ACCOUNT:role/AdminRole'

# Find all principals that can escalate to admin
pmapper analysis

# Visualize the privilege escalation graph
pmapper visualize --filetype png

# Check specific escalation paths
pmapper query 'can arn:aws:iam::ACCOUNT:user/test-user do iam:CreatePolicyVersion with *'
pmapper query 'can arn:aws:iam::ACCOUNT:user/test-user do sts:AssumeRole with arn:aws:iam::ACCOUNT:role/*'

Step 4: Test Cross-Account Role Assumption

Evaluate cross-account trust policies for misconfigured role assumptions that allow unauthorized escalation.

# List all roles and their trust policies

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