WeeklyTalk · Episode #191 · 11/12/2026

The Key Was 4: How a Certification Authority Lost People's Trust

In October, it came to light that the certification authority eMudhra had generated eight of its intermediate certificates using keys that were easy to guess.

A private key intended to secure millions of connections on the Internet was simply „4“. In October, it came to light that the certification authority eMudhra had generated eight of its intermediate certificates using keys that were easy to guess, despite having passed an audit. Thomas and Timo reconstruct the incident, place it in the context of nearly two decades of CA failures, and explain how to identify a trustworthy certification authority.

The Key Was 4: How a Certification Authority Lost People's Trust