I’ve factored the RSA keys of a Certificate Authority... from the 90s
Summary
The author demonstrates that 512-bit RSA roots from late 1990s PKI can be factored using public tools, reconstructing private keys from old Netscape root certificates. The piece walks through selecting targets, performing factoring with CADO-NFS on commodity hardware, and setting up a test TLS service using the recovered keys, highlighting security risks of legacy keys. It also notes public hosting of results and discusses TLS compatibility issues and SSL Labs evaluations.