Timeline
- 8.5
Eight Bits of Trust: eMudhra's CA keys cracked in milliseconds
The private keys behind eight of eMudhra's intermediate CA certificates were found to be integers smaller than 256 — effectively eight bits of entropy — and all eight were recovered in about 11 milliseconds. The finding was disclosed on October 20 at emudhra.we-have-a-problem.com, and major browsers and software platforms have begun blocking the affected certificates. Because the weak keys were effectively public from the day the certificates were issued, anyone could have forged certificates chaining to a trusted root — and devices that cannot update their CA bundles remain exposed. According to the original reporter, the discovery came out of Google's open-source paranoid_crypto tool, run essentially out of the box against the CCADB corpus before subscriber certificates were examined. A follow-up sweep of all existing CCADB certificates reportedly turned up no further hits, and Chrome found no rogue certificates in Certificate Transparency logs.
- 8.0
EMudhra Intermediate CA Compromise
eMudhra's intermediate ECC certificate authorities were found to have effectively guessable private keys, reportedly single-byte values (one of them literally "4"), traced to a flaw in the KGC script used on a specific day to create those ECC issuers. Browser vendors responded by revoking trust in the affected intermediates, while non-browser TLS clients that do not use modern revocation tooling remain exposed. Because the intermediate CAs were publicly trusted, anyone who could guess the keys could have forged certificates for arbitrary domains, and that risk falls unevenly across the ecosystem. A Mozilla engineer said Firefox users were protected automatically within a couple of hours via OneCRL, with Chrome, Apple and Microsoft operating similar tooling, but "for the rest of the ecosystem, there has been little to no investment in revocation." In Mozilla bug 2083449, eMudhra said its preliminary assessment found "a flaw in the KGC script that was used on that specific day to create these ECC issuers," and that review of the KGC code and HSM keys so far indicates a set of original ECC keys was created onboard as expected plus an approved deviation to its usual KGC. Community reports describe eight affected CAs, and one commenter said the keys were allegedly found at a public repository URL, while noting uncertainty about whether the artifacts show stolen keys or a weak generation process.