4G LTE Network Exploits

Practical attack techniques targeting 4G LTE networks, including Diameter vulnerabilities, GTP attacks, radio interface exploits, and VoLTE security issues.

Diameter Exploits
GTP Attacks
Radio Interface
VoLTE Security
EPC Vulnerabilities
4G Network Background
S6a Interface Information Disclosure
Exploiting the S6a interface to extract subscriber data

This exploit targets the S6a interface between the MME and HSS to extract subscriber information through malformed Diameter commands.

Technical Details:

  • Crafting malicious Authentication Information Request (AIR) messages
  • Exploiting insufficient validation of AVP values
  • Extracting IMSI, authentication vectors, and subscriber profiles
Difficulty: Medium
HSS Authentication Bypass
Bypassing authentication mechanisms in the HSS

This exploit targets weaknesses in the authentication process between the MME and HSS, allowing attackers to bypass authentication checks.

Technical Details:

  • Manipulating Authentication-Information-Answer (AIA) messages
  • Injecting pre-computed authentication vectors
  • Exploiting improper session handling in Diameter implementations
Difficulty: High
Diameter Command Injection
Injecting malicious commands into Diameter sessions

This technique involves injecting unauthorized Diameter commands into existing sessions to manipulate subscriber data or network behavior.

Technical Details:

  • Session hijacking through Diameter routing manipulation
  • Injecting Update-Location-Request (ULR) messages
  • Modifying subscriber profiles through Insert-Subscriber-Data-Request (IDR)
Difficulty: High
Diameter Routing Manipulation
Manipulating Diameter routing to redirect traffic

This exploit targets the Diameter routing infrastructure to redirect traffic through malicious nodes or perform man-in-the-middle attacks.

Technical Details:

  • Exploiting Diameter Edge Agent (DEA) configuration weaknesses
  • Manipulating Diameter Routing Agent (DRA) tables
  • Injecting false routing information through Capabilities-Exchange messages
Difficulty: Medium

Advanced 4G LTE Exploit Techniques

Multi-Vector Attack Chains
Combining multiple exploits for advanced attacks

Advanced attackers often chain multiple vulnerabilities to achieve more sophisticated attacks. For example, combining Diameter routing manipulation with GTP tunnel hijacking can allow complete control over user traffic while evading detection mechanisms.

Example Attack Chain:

  1. Exploit Diameter routing to redirect S6a traffic
  2. Extract authentication vectors from HSS communications
  3. Use obtained vectors to authenticate to the network
  4. Hijack GTP tunnels to intercept user traffic
Virtualization Layer Attacks
Targeting NFV infrastructure in 4G networks

Modern 4G networks often use Network Function Virtualization (NFV) for core components. This introduces additional attack vectors targeting the virtualization layer itself.

Common Techniques:

  • Hypervisor escape vulnerabilities
  • Virtual network function (VNF) manipulation
  • Management and orchestration (MANO) exploitation
  • Inter-VM attacks in multi-tenant environments

Tools for 4G LTE Security Testing

Radio Interface Testing
  • srsRAN

    Open-source 4G LTE implementation for software-defined radio

  • OsmocomBB

    Open source GSM baseband software implementation

  • LTE-Cell-Scanner

    Tool for scanning and analyzing LTE cells

  • IMSICATCHER

    Tool for IMSI catching and analysis

Core Network Testing
  • Diameter Testing Tool

    Framework for testing Diameter protocol implementations

  • GTP Toolkit

    Suite for GTP protocol testing and exploitation

  • EPC Fuzzer

    Fuzzing tool for EPC interfaces and protocols

  • S1APTester

    Testing tool for S1 Application Protocol

VoLTE Testing
  • SIPp

    SIP protocol test tool and traffic generator

  • IMS Bench SIPp

    Extended version of SIPp for IMS testing

  • VoLTE Fuzzer

    Specialized fuzzing tool for VoLTE interfaces

  • RTP/SRTP Analysis Tools

    Tools for analyzing media streams in VoLTE

Mitigation Recommendations

To protect against the exploits described on this page, network operators should implement the following security measures:

Diameter Security

  • Implement Diameter Edge Agents (DEA) with proper filtering
  • Use IPsec or TLS for all Diameter connections
  • Deploy Diameter Routing Agents with security policies
  • Implement proper AVP validation and filtering

GTP Security

  • Implement GTP firewalls with deep packet inspection
  • Validate TEID values and sequence numbers
  • Monitor for abnormal GTP traffic patterns
  • Implement rate limiting for GTP control messages

Radio Interface Security

  • Disable null encryption (EEA0) except where required
  • Implement rogue base station detection
  • Use IMSI catching detection systems
  • Implement proper key management for radio interfaces

VoLTE Security

  • Implement SIP header validation and filtering
  • Use TLS for SIP signaling
  • Implement SRTP for media encryption
  • Validate caller ID information across network boundaries

Related Resources

4G LTE Methodology

Learn about systematic approaches to testing 4G LTE network security.

View Methodology
4G LTE Attack Vectors

Explore the various attack vectors affecting 4G LTE networks.

View Attack Vectors
Diameter Security

Deep dive into Diameter protocol security issues and testing.

View Diameter Security