  The rise of large-scale quantum computing poses a significant threat to
traditional cryptographic security measures. Quantum attacks undermine current
asymmetric cryptographic algorithms, rendering them ineffective. Even symmetric
key cryptography is vulnerable, albeit to a lesser extent, suggesting longer
keys or extended hash functions for security. Thus, current cryptographic
solutions are inadequate against emerging quantum threats. Organizations must
transition to quantum-safe environments with robust continuity plans and
meticulous risk management. This study explores the challenges of migrating to
quantum-safe cryptographic states, introducing a comprehensive security risk
assessment framework. We propose a security risk assessment framework that
examines vulnerabilities across algorithms, certificates, and protocols
throughout the migration process (pre-migration, during migration,
post-migration). We link these vulnerabilities to the STRIDE threat model to
assess their impact and likelihood. Then, we discuss practical mitigation
strategies for critical components like algorithms, public key infrastructures,
and protocols. Our study not only identifies potential attacks and
vulnerabilities at each layer and migration stage but also suggests possible
countermeasures and alternatives to enhance system resilience, empowering
organizations to construct a secure infrastructure for the quantum era. Through
these efforts, we establish the foundation for enduring security in networked
systems amid the challenges of the quantum era.
