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I've factored the RSA keys of a Certificate Authority from the 90s

Security researcher factored two 512-bit RSA root CA keys from defunct 1990s certificate authority E-Certify using CADO-NFS on a desktop in roughly 30 hours each.

A researcher extracted legacy root certificates from archived Netscape and Internet Explorer installers, identifying two 512-bit RSA roots shipped with Netscape 4.51 in 1999 by the defunct Canadian CA E-Certify. Using CADO-NFS on a Ryzen 9 5950X desktop, the keys were factored in 32 and 29 hours respectively, allowing private key reconstruction. The work comes shortly after RSA-260 (862-bit) was factored, the largest known factorization to date. The researcher also built a legacy TLS server and published keys and tools on GitHub.

Necessary or Sufficient? Evaluating LLM Explanations With Behavioural Evidence

New framework tests whether LLM-cited explanation factors are necessary or sufficient, finding weak correlation across Claude, GPT, and Gemini models.

An arXiv paper introduces black-box intervention tests measuring whether factors LLMs cite in their explanations are necessary or sufficient for their outputs in agent oversight workflows. Across eight models from the Claude, GPT, and Gemini families, Spearman correlations between cited rankings and measured influence ranged from 0.349-0.354 (advisor recommendation) to 0.431-0.580 (prompt monitoring). Uncited factors scored above the lowest cited factor in up to 57.6% of advisor responses, showing cited top-three factors do not reliably identify the most influential inputs.