Cryptography researcher Matthew McPherrin factorized 512-bit RSA certificates issued by Canadian CA E-Certify using an AMD Ryzen 9 5950X processor in 32–29 hours. While demonstrating that legacy 512-bit keys (embedded in Netscape 4.51 in 1999) are cryptographically broken, the practical risk is minimal: E-Certify certificates expired in 2003. The finding underscores why NIST deprecated RSA-1024 in 2010, recommending RSA-2048 instead—relevant context for Thai SMEs reviewing legacy security infrastructure.