Critical Infrastructure

IMS Attacks & Security Analysis

Advanced IP Multimedia Subsystem attack methodologies, VoLTE security vulnerabilities, and comprehensive penetration testing techniques for telecommunications infrastructure.

70
Attack Vectors
2
Critical Severity
2
Known CVEs
3
Security Tools

IMS Architecture & Components

Core Network Functions
  • P-CSCF (Proxy Call Session Control Function)
  • S-CSCF (Serving Call Session Control Function)
  • I-CSCF (Interrogating Call Session Control Function)
  • HSS (Home Subscriber Server)
Protocol Stack
  • SIP (Session Initiation Protocol)
  • Diameter (Authentication & Authorization)
  • RTP/SRTP (Media Transport)
  • HTTP/2 (Service Layer)
IMS Architecture Overview

Detailed VoLTE Attack Scenarios

SIP Registration Hijacking
Critical
Authentication
CVSS Score
9.1
RTP Stream Manipulation
High
Media Plane
CVSS Score
8.3
Emergency Call Manipulation
Critical
Emergency Services
CVSS Score
9.8
SIP Registration Hijacking
Attackers intercept and manipulate SIP REGISTER messages to hijack user registrations in the IMS core, allowing them to impersonate legitimate subscribers.
Critical
CVSS: 9.1

This attack exploits weaknesses in SIP authentication mechanisms by intercepting REGISTER requests and responses. The attacker positions themselves between the UE and P-CSCF to capture authentication challenges and either replay them or manipulate the registration process to redirect calls to attacker-controlled endpoints.

Progress1 / 5

Attack Execution Steps

1
Network Positioning

Position attacker infrastructure in the signaling path between UE and P-CSCF

Technical Details:

Deploy rogue base station or compromise network infrastructure to intercept SIP traffic

Tools:
OpenBTS
srsLTE
Network TAPs
2
Traffic Interception

Monitor and capture SIP REGISTER messages

Technical Details:

Use packet capture tools to monitor SIP traffic on UDP port 5060 or TLS port 5061

Tools:
Wireshark
tcpdump
SIPp
3
Authentication Analysis

Analyze captured authentication challenges and responses

Technical Details:

Extract WWW-Authenticate headers and analyze digest authentication parameters

Tools:
SIPVicious
Custom scripts
4
Registration Manipulation

Craft malicious REGISTER messages to hijack registration

Technical Details:

Create spoofed REGISTER requests with modified Contact headers pointing to attacker infrastructure

Tools:
SIPp
Custom SIP clients
5
Call Redirection

Redirect incoming calls to attacker-controlled endpoints

Technical Details:

Respond to INVITE messages and establish media sessions with attacker infrastructure

Tools:
Asterisk
FreeSWITCH
Custom SIP proxy

Comprehensive Mitigation Framework

Network Security
Critical Priority

Authentication and Authorization
Critical Priority

Encryption and Privacy
High Priority

Quick Security Checklist
Essential security measures for VoLTE protection
Network Security
  • SIP Firewall deployed
  • Network segmentation
  • Access controls
Encryption
  • TLS for signaling
  • SRTP for media
  • Key management
Monitoring
  • Real-time monitoring
  • Anomaly detection
  • Incident response

VoLTE Security Mitigation Strategies

Critical
Network Security
SIP Firewall and Deep Packet Inspection
2-4 weeks
Effectiveness
Cost
Complexity
Risk Reduction85%
Critical
Encryption
SRTP Media Encryption
1-2 weeks
Effectiveness
Cost
Complexity
Risk Reduction90%
High
Network Security
Network Segmentation and Isolation
4-8 weeks
Effectiveness
Cost
Complexity
Risk Reduction80%
SIP Firewall and Deep Packet Inspection
Deploy specialized SIP firewalls with deep packet inspection capabilities to filter malicious SIP traffic and prevent protocol-based attacks.
Critical
Network Security
Effectiveness
High
Cost
Medium
Complexity
Medium
Timeline
2-4 weeks
Implementation Roadmap
Recommended approach for implementing VoLTE security mitigations
Phase 1
Critical Security
Implement SIP firewalls and SRTP encryption for immediate protection
Phase 2
Network Hardening
Deploy network segmentation and advanced monitoring capabilities
Phase 3
Advanced Protection
Implement AI-based threat detection and automated response systems

Attack Categories & Vectors

VoLTE Security
Critical
Voice over LTE security vulnerabilities and attack methodologies
Attack Techniques18
SIP
RTP
Diameter
+1
VoWiFi Security
High
Voice over WiFi security vulnerabilities and attack methodologies
Attack Techniques14
SIP
IPSec
IKEv2
+1
IMS Core Attacks
Critical
IMS core infrastructure security vulnerabilities
Attack Techniques22
SIP
Diameter
HTTP/2
+1
SIP Protocol Attacks
High
Session Initiation Protocol vulnerabilities in IMS context
Attack Techniques16
SIP
SDP
RTP
+1

Security Testing Tools

SIPp
SIP protocol test tool and traffic generator
Type
SIP Testing
PlatformLinux/Windows/macOS
Load Testing
Protocol Testing
Attack Simulation
SIPVicious
SIP security testing suite
Type
SIP Security
PlatformLinux/Windows/macOS
SIP Scanning
Vulnerability Testing
Security Assessment
OpenIMS Core
Open source IMS core network implementation
Type
IMS Testing
PlatformLinux
IMS Testing
Research
Development

CVE Database

CVE-2023-28771
Critical
CVSS: 9.8
IMS Core SIP Stack Buffer Overflow

Buffer overflow vulnerability in IMS core SIP stack allowing remote code execution

Affected Components
P-CSCF
S-CSCF
I-CSCF
Impact
Remote Code Execution
Service Disruption
Data Breach
CVE-2023-45892
High
CVSS: 8.1
VoLTE Call Setup Authentication Bypass

Authentication bypass in VoLTE call setup allowing unauthorized call establishment

Affected Components
VoLTE Stack
IMS Client
Impact
Unauthorized Access
Call Interception
Identity Theft

Standards & Compliance Framework

GSMA Security
GSM Association - Mobile Security Guidelines

Official GSMA security guidelines for mobile networks, including IMS security recommendations and VoLTE security best practices.

Key Documents:
  • • FS.31 - IMS Security Guidelines
  • • FS.19 - VoLTE Security Guide
  • • FS.40 - Network Equipment Security
Visit GSMA Security
3GPP Standards
3rd Generation Partnership Project

Technical specifications for mobile telecommunications, including IMS architecture and security requirements.

Key Specifications:
  • • TS 23.228 - IMS Architecture
  • • TS 33.203 - IMS Security
  • • TS 24.229 - IMS Call Control
Visit 3GPP
ETSI Standards
European Telecommunications Standards Institute

European standards for telecommunications security, including IMS and VoLTE security specifications.

Key Standards:
  • • TS 187 001 - IMS Security
  • • TS 133 203 - IMS Security
  • • ES 203 119 - VoLTE Security
Visit ETSI
NIST Cybersecurity
National Institute of Standards and Technology

US federal cybersecurity standards and guidelines applicable to telecommunications infrastructure.

Key Publications:
  • • SP 800-53 - Security Controls
  • • SP 800-171 - CUI Protection
  • • Cybersecurity Framework
Visit NIST
ENISA Guidelines
European Union Agency for Cybersecurity

EU cybersecurity guidelines and threat landscape reports for telecommunications sector.

Key Reports:
  • • 5G Security Guidelines
  • • Telecom Threat Landscape
  • • ICS/SCADA Security
Visit ENISA
ITU-T Security
International Telecommunication Union

International standards for telecommunications security and network protection.

Key Recommendations:
  • • X.805 - Network Security
  • • X.1051 - VoIP Security
  • • Y.2701 - NGN Security
Visit ITU-T SG17
IMS Security Compliance Matrix
Mapping of IMS security requirements to international standards and regulations
Security Domain3GPPGSMAETSINISTENISA
Authentication & AuthorizationTS 33.203FS.31TS 187 001SP 800-635G Guidelines
Encryption & Key ManagementTS 33.210FS.19TS 133 203SP 800-57Crypto Guidelines
Network SecurityTS 33.401FS.40TS 103 523SP 800-53Network Security
VoLTE SecurityTS 24.229FS.19ES 203 119SP 800-58VoIP Security
Incident ResponseTS 32.111FS.11TS 132 111SP 800-61Incident Handling
Privacy ProtectionTS 33.501FS.26TS 133 501Privacy FrameworkGDPR Guidelines

IMS Security Compliance Checker

Overall Status
Non-Compliant
0 of 8 requirements met
Critical Requirements
0/3
Critical items completed
Actions
Implement AKA-based authentication
Critical
3GPP TS 33.203
Authentication & Authorization

Authentication and Key Agreement (AKA) must be implemented for IMS access

Implementation Guidance:

Configure HSS with proper AKA vectors and implement AKA procedures in P-CSCF

Enable SRTP for media encryption
Critical
GSMA FS.19
Encryption

All media streams must be encrypted using SRTP

Implementation Guidance:

Configure media gateways to negotiate SRTP and implement proper key management

Implement network segmentation
High
NIST SP 800-53
Network Security

IMS components must be properly segmented from other network elements

Implementation Guidance:

Deploy firewalls and VLANs to isolate IMS core functions

Enable SIP over TLS
Critical
3GPP TS 24.229
SIP Security

SIP signaling must be protected using TLS encryption

Implementation Guidance:

Configure all SIP entities to use TLS and implement proper certificate management

Implement security monitoring
High
ENISA Guidelines
Monitoring

Real-time security monitoring must be implemented

Implementation Guidance:

Deploy SIEM solutions and configure security event correlation

Establish incident response procedures
High
NIST SP 800-61
Incident Response

Formal incident response procedures must be established

Implementation Guidance:

Develop incident response playbooks and train response teams

Implement privacy protection
Medium
GSMA FS.26
Privacy

User privacy must be protected according to applicable regulations

Implementation Guidance:

Implement data minimization and user consent mechanisms

Enable comprehensive logging
High
ITU-T X.1051
Audit & Logging

All security-relevant events must be logged

Implementation Guidance:

Configure centralized logging and implement log retention policies

Frequently Asked Questions

Professional IMS Security Assessment

Need expert IMS security testing? Our team provides comprehensive penetration testing services for telecommunications infrastructure with advanced attack simulation and vulnerability assessment.

Security Metrics
Total Attacks
70
Critical Severity
2
High Severity
2
Known CVEs
2
Security Tools
3
Latest Updates
New CVE-2025-32433
IMS Core vulnerability discovered
2 days ago
VoLTE Security Update
Enhanced testing methodology
1 week ago
Tool Update: SIPp v3.7
New features for IMS testing
2 weeks ago

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