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5G Attacks

SUCI Attacks

HIGH SEVERITY
Overview

Subscription Concealed Identifier (SUCI) attacks attempt to compromise the 5G privacy mechanism designed to protect subscriber identities through cryptographic concealment.

Technical Overview

5G uses SUCI to protect SUPI (Subscription Permanent Identifier) through public key encryption. Attacks target the encryption implementation, key management, or exploit scenarios where SUPI must be transmitted in cleartext for backward compatibility.

Impact
Potential consequences of this attack
  • Subscriber identity exposure
  • Privacy protection bypass
  • Enabling of tracking and surveillance
  • Correlation with legacy network identifiers
  • Targeted attack facilitation
Attack Vectors
Methods used to execute this attack
  • Cryptographic implementation vulnerabilities
  • Key management exploitation
  • Forcing fallback to SUPI transmission
  • Side-channel attacks on SUCI generation
  • Exploiting null-scheme SUCI
Attack Methodology
Step-by-step attack execution process
  1. 1Deploy rogue gNodeB to intercept SUCI
  2. 2Analyze SUCI encryption implementation
  3. 3Attempt to force SUPI transmission
  4. 4Exploit backward compatibility scenarios
  5. 5Correlate SUCI with other identifiers
  6. 6Build subscriber identity database
Mitigations & Defense
Protective measures and countermeasures
  • Implement strong SUCI encryption schemes
  • Avoid null-scheme SUCI in production
  • Secure key management infrastructure
  • Monitor for SUPI transmission attempts
  • Implement additional privacy layers
  • Regular security audits of SUCI implementation
Real-World Examples
Known incidents and use cases
  • Security research on 5G privacy
  • Theoretical attacks on SUCI schemes
  • Implementation vulnerability discoveries
  • Backward compatibility exploitation