Factoring RSA Keys with Many Zeros

Research uncovered a new class of weak RSA keys with many regularly spaced zero blocks present in real-world key collections (Certificate Transparency logs, internet TLS/SSH scans, PGP keys). Patterns appear in certificates for large organizations and in keys produced by specific software (CompleteFTP and some NetApp-related keys); affected versions are listed. The weakness could make those keys factorable, researchers reported findings to vendors, but the article presents no confirmed evidence of active exploitation.