UCaaS Fraud Protection

UCaaS Threat Landscape

UCaaS platforms provide cloud-based voice, messaging, video, and collaboration services to businesses. The combination of telecommunications capabilities and multi-tenant cloud architecture creates a complex attack surface that requires comprehensive protection.

Why UCaaS Is Targeted

• Direct monetization — Voice minutes can be converted to cash via toll fraud
• High-value targets — Business accounts have more resources to exploit
• Multiple attack vectors — Voice, SMS, fax, and messaging all have value
• Credential reuse — Business users often use compromised passwords
• Complex permissions — Admin accounts enable widespread abuse

Common Attack Scenarios

Account Security Architecture

Authentication Hardening

UCaaS accounts require strong authentication to prevent compromise:

class UCaaSAuthenticationPolicy:
    """
    Authentication requirements for UCaaS platform.
    Different requirements by account type and action.
    """
    POLICIES = {
        'user': {
            'mfa_required': True,
            'session_timeout': 3600,  # 1 hour
            'password_rotation': 90,  # days
            'concurrent_sessions': 3
        },
        'admin': {
            'mfa_required': True,
            'mfa_type': ['hardware_key', 'authenticator_app'],  # No SMS
            'session_timeout': 1800,  # 30 minutes
            'password_rotation': 30,
            'concurrent_sessions': 1,
            'ip_allowlist_required': True
        },
        'api': {
            'api_key_required': True,
            'ip_allowlist_required': True,
            'rate_limiting': True,
            'key_rotation': 90
        }
    }

    def verify_authentication(self, user, action):
        policy = self.POLICIES.get(user.role, self.POLICIES['user'])

        # Check MFA
        if policy['mfa_required'] and not user.mfa_verified:
            return {'allowed': False, 'reason': 'mfa_required'}

        # Check session age
        if user.session_age > policy['session_timeout']:
            return {'allowed': False, 'reason': 'session_expired'}

        # Check concurrent sessions
        if user.active_sessions > policy['concurrent_sessions']:
            return {'allowed': False, 'reason': 'too_many_sessions'}

        return {'allowed': True}

Phone-Based Identity Verification

For user and customer identity, leverage phone intelligence:

def verify_customer_identity(phone_number, customer_id):
    """
    Verify customer phone ownership and detect account takeover.
    """
    # Get current phone intelligence
    intel = veriroute_lookup(phone_number, lrn=True)

    # Get baseline from customer record
    baseline = get_customer_phone_baseline(customer_id)

    risk_signals = []

    # Carrier change detection (SIM swap indicator)
    if intel['carrier'] != baseline['carrier']:
        risk_signals.append({
            'type': 'carrier_change',
            'severity': 'high',
            'action': 'step_up_auth'
        })

    # Recent porting (account takeover indicator)
    if is_recently_ported(intel.get('lrn_activation_date'), days=30):
        risk_signals.append({
            'type': 'recent_port',
            'severity': 'critical',
            'action': 'manual_verification'
        })

    # Line type change
    if intel['line_type'] != baseline['line_type']:
        risk_signals.append({
            'type': 'line_type_change',
            'severity': 'medium',
            'action': 'notify_security'
        })

    return {
        'verified': len([s for s in risk_signals if s['severity'] == 'critical']) == 0,
        'risk_signals': risk_signals,
        'recommended_action': determine_action(risk_signals)
    }

Voice Fraud Prevention

Call Pattern Analysis

Monitor calling patterns for fraud indicators:

class VoiceFraudDetector:
    """
    Real-time analysis of voice traffic for fraud patterns.
    """
    RULES = {
        'international_burst': {
            'description': 'Sudden spike in international calls',
            'threshold': 10,
            'window_seconds': 300,
            'severity': 'critical'
        },
        'premium_rate': {
            'description': 'Calls to premium rate numbers',
            'threshold': 1,
            'window_seconds': 86400,
            'severity': 'critical'
        },
        'high_cost_destinations': {
            'description': 'Calls to high-cost countries',
            'destinations': ['53', '252', '371', '960'],  # Cuba, Somalia, etc.
            'threshold': 3,
            'window_seconds': 3600,
            'severity': 'high'
        },
        'after_hours': {
            'description': 'International calls outside business hours',
            'hours': range(22, 6),  # 10 PM to 6 AM
            'threshold': 5,
            'window_seconds': 3600,
            'severity': 'medium'
        }
    }

    def analyze_call(self, customer_id, call_record):
        violations = []

        for rule_name, rule in self.RULES.items():
            if self._check_rule(customer_id, call_record, rule):
                violations.append({
                    'rule': rule_name,
                    'description': rule['description'],
                    'severity': rule['severity']
                })

        return {
            'allow_call': not any(v['severity'] == 'critical' for v in violations),
            'violations': violations,
            'action': self._determine_action(violations)
        }

    def _determine_action(self, violations):
        if not violations:
            return 'allow'

        severities = [v['severity'] for v in violations]

        if 'critical' in severities:
            return 'block_and_alert'
        elif 'high' in severities:
            return 'require_confirmation'
        else:
            return 'log_and_allow'

Pre-Call Number Screening

Check destination numbers before connecting calls:

def screen_outbound_call(destination, customer):
    """
    Screen destination number before connecting.
    """
    # Get number intelligence
    intel = veriroute_lookup(destination, lrn=True)

    # Check against customer's allowed destinations
    if not customer.can_call_destination(intel['country_code']):
        return {
            'allow': False,
            'reason': 'destination_not_allowed',
            'message': 'International calling to this destination is not enabled.'
        }

    # Check for premium rate indicators
    if intel.get('line_type') == 'premium':
        return {
            'allow': False,
            'reason': 'premium_rate_blocked',
            'message': 'Calls to premium rate numbers are blocked.'
        }

    # Check carrier reputation
    if intel.get('carrier') in HIGH_RISK_CARRIERS:
        log_suspicious_call(customer, destination, intel)
        # Allow but monitor
        return {'allow': True, 'monitoring': 'enhanced'}

    return {'allow': True}

Messaging Protection

SMS Fraud Prevention

Protect against messaging abuse:

class SMSFraudProtection:
    """
    Multi-layer protection for outbound messaging.
    """
    def screen_message(self, customer_id, destination, message_type):
        # Rate limiting
        rate_check = self._check_rate_limits(customer_id, destination)
        if not rate_check['allowed']:
            return rate_check

        # Destination validation
        intel = veriroute_lookup(destination, lrn=True, spam=True)

        # Block non-mobile destinations for SMS
        if intel['line_type'] == 'landline':
            return {
                'allowed': False,
                'reason': 'cannot_receive_sms',
                'suggestion': 'Use voice for landline numbers'
            }

        # Check for SMS pumping indicators
        if self._detect_sms_pumping(customer_id, destination):
            return {
                'allowed': False,
                'reason': 'sms_pumping_detected',
                'action': 'account_review'
            }

        # Content filtering (for A2P)
        if message_type == 'a2p':
            content_check = self._check_content_compliance(customer_id)
            if not content_check['compliant']:
                return content_check

        return {'allowed': True}

    def _detect_sms_pumping(self, customer_id, destination):
        """Detect SMS pumping to premium destinations."""
        # Check for pattern: many messages to sequential numbers
        recent_destinations = self._get_recent_destinations(
            customer_id,
            minutes=60
        )

        # Sequential number detection
        dest_digits = [int(d[-4:]) for d in recent_destinations if d[-4:].isdigit()]
        if self._has_sequential_pattern(dest_digits):
            return True

        # Same prefix, many suffixes (number range testing)
        prefixes = [d[:-4] for d in recent_destinations]
        if len(set(prefixes)) == 1 and len(recent_destinations) > 20:
            return True

        return False

Caller ID Verification

Ensure legitimate caller ID usage:

def verify_caller_id(customer_id, requested_caller_id):
    """
    Verify customer has rights to use caller ID.
    STIR/SHAKEN attestation level determination.
    """
    # Get customer's verified numbers
    verified_dids = get_customer_verified_dids(customer_id)

    if requested_caller_id in verified_dids:
        return {
            'allowed': True,
            'attestation': 'A',  # Full attestation
            'reason': 'verified_did'
        }

    # Check if it's an associated number (e.g., main business line)
    associated = get_associated_numbers(customer_id)
    if requested_caller_id in associated:
        return {
            'allowed': True,
            'attestation': 'B',  # Partial attestation
            'reason': 'associated_number'
        }

    # Not verified - either block or use gateway attestation
    return {
        'allowed': False,
        'reason': 'unverified_caller_id',
        'message': 'Please verify this number before using as caller ID.',
        'action': 'verify_number'
    }

Multi-Tenant Security

Tenant Isolation

Prevent cross-tenant attacks and abuse spillover:

class TenantIsolation:
    """
    Enforce tenant boundaries for security and resource isolation.
    """
    def __init__(self):
        self.tenant_limits = {}

    def enforce_isolation(self, tenant_id, resource_type, action):
        # Verify tenant context
        if not self._verify_tenant_context(tenant_id):
            raise SecurityException("Tenant context violation")

        # Apply tenant-specific limits
        limits = self.get_tenant_limits(tenant_id, resource_type)

        usage = self.get_current_usage(tenant_id, resource_type)
        if usage >= limits['max']:
            return {
                'allowed': False,
                'reason': 'tenant_limit_exceeded',
                'current': usage,
                'limit': limits['max']
            }

        return {'allowed': True}

    def get_tenant_limits(self, tenant_id, resource_type):
        """
        Get resource limits based on tenant subscription tier.
        """
        tier = self.get_tenant_tier(tenant_id)

        limits = {
            'basic': {
                'concurrent_calls': 10,
                'sms_per_hour': 100,
                'international_minutes_daily': 60,
                'dids': 5
            },
            'professional': {
                'concurrent_calls': 50,
                'sms_per_hour': 1000,
                'international_minutes_daily': 500,
                'dids': 25
            },
            'enterprise': {
                'concurrent_calls': 500,
                'sms_per_hour': 10000,
                'international_minutes_daily': 5000,
                'dids': 100
            }
        }

        return limits.get(tier, limits['basic'])[resource_type]

Cross-Tenant Abuse Prevention

Monitor for abuse that affects platform reputation:

• IP reputation tracking — Block tenants using known bad IPs
• Caller ID reputation — Monitor for spam complaints on tenant DIDs
• Content monitoring — Detect phishing/spam in messaging
• Behavior analytics — Identify anomalous usage patterns

Real-Time Monitoring and Response

Monitoring Dashboard

Essential metrics for fraud detection:

Automated Response

class FraudResponseAutomation:
    """
    Automated response to detected fraud patterns.
    """
    RESPONSES = {
        'toll_fraud_detected': {
            'immediate': ['block_international', 'notify_admin', 'log_incident'],
            'investigation': ['export_cdrs', 'identify_compromised_accounts'],
            'recovery': ['reset_credentials', 'review_permissions']
        },
        'account_compromise': {
            'immediate': ['lock_account', 'revoke_sessions', 'notify_user'],
            'investigation': ['audit_recent_activity', 'check_data_access'],
            'recovery': ['require_identity_verification', 'reset_mfa']
        },
        'spam_campaign': {
            'immediate': ['suspend_messaging', 'notify_admin'],
            'investigation': ['analyze_message_content', 'identify_recipients'],
            'recovery': ['verify_legitimate_use', 'implement_content_filtering']
        }
    }

    def execute_response(self, fraud_type, tenant_id, incident_data):
        response_plan = self.RESPONSES.get(fraud_type)
        if not response_plan:
            return self._escalate_to_human(fraud_type, tenant_id)

        results = {'actions_taken': []}

        # Execute immediate actions
        for action in response_plan['immediate']:
            result = self._execute_action(action, tenant_id, incident_data)
            results['actions_taken'].append({
                'action': action,
                'success': result['success'],
                'timestamp': datetime.utcnow()
            })

        # Queue investigation tasks
        for task in response_plan['investigation']:
            self._queue_investigation(task, tenant_id, incident_data)

        return results

UCaaS Fraud Protection Checklist

Compliance Considerations

UCaaS fraud protection must align with regulatory requirements:

• STIR/SHAKEN — FCC mandate for caller ID authentication
• TCPA — Consent requirements for messaging and calling
• 10DLC — Campaign registration for A2P messaging
• Do Not Call — DNC list scrubbing requirements
• GDPR/CCPA — Privacy requirements for monitoring and logging

Work with legal counsel to ensure fraud prevention measures comply with applicable regulations in your operating jurisdictions.

Vendor and Carrier Integration

Leverage carrier and vendor capabilities:

• Carrier fraud APIs — Access carrier-side fraud detection
• Phone intelligence providers — Real-time number validation
• Threat intelligence feeds — Known fraudulent numbers and IPs
• Industry consortiums — Share fraud intelligence with peers