Overview
- A security researcher who reported the issue on October 17 showed eight intermediate CA private keys could be rebuilt in seconds because they were created with values under 256 rather than true randomness.
- The weak keys were produced during an April 30, 2025 key-generation ceremony and included single-byte values such as 4, 56 and 237, which made brute-force recovery trivial.
- Google, Mozilla, Apple and Microsoft moved to block or distrust the affected intermediates and Google plans to remove the related emSign ECC Root CA - G3 from Chrome on October 27, while vendors and package projects have pushed updates.
- eMudhra revoked the eight intermediates, said most were not used in production, and announced it will exit its global website SSL/TLS business as Indian regulators including MeitY and CERT-In open investigations.
- No confirmed real-world exploitation has been published so far but remediation is complex because many apps, IoT devices and bespoke trust stores may still accept the compromised chains and will need updates or certificate replacement.