Factoring RSA Keys with Many Zeros - Schneier on Security

Interesting research on a new class of weak RSA keys: keys with lots of zeros. It turns out that these keys are out in the wild. The badkeys project is an open-source service that checks public keys for known vulnerabilities. While developing this tool, Hanno collected a massive number of real-world keys from public sources, including Certificate Transparency logs, internet-wide TLS and SSH scans, PGP keys, and many others. By searching this dataset for unexpectedly sparse RSA moduli, we uncovered a large number of keys in the wild with the patterns in Figure 1...

Raccontata daschneier.com