Indian certificate authority eMudhra is withdrawing from the global SSL/TLS certificate business after eight of its intermediate certificate authority private keys turned out to be tiny numbers anyone could guess, one of them literally 4. The incident has now been assigned the identifier CVE-2026-111943.

The certificates used P-384 elliptic-curve cryptography, where a private key should be a random 384-bit number. Instead, the eight keys were 4, 56, 66, 115, 155, 156, 230 and 237. Scott Helme recovered all eight from their public keys on a laptop in under a second.

A script error in the key ceremony

The certificates were created at a key generation ceremony on 30 April 2025. eMudhra says a flaw in the ceremony script's wrap-and-unwrap step produced a second set of weak keys alongside the good ones, and the weak keys were used. They were effectively public from the day the certificates existed and remained trusted for about 17 months.

A researcher known as Wayne reported the problem to the browser root programmes on 17 October 2026, proving it by signing a message with each key. Firefox and Chrome blocked the compromised certificates the same day, and Microsoft followed on 20 October. Mozilla has since removed the emSign ECC Root CA - G3 root; around 30,000 customer certificates must be replaced.

Exit from the TLS business

eMudhra has revoked the certificates and says none issued end-entity certificates, and only one was ever deployed. CERT-In says its domestic digital signature and eSign infrastructure was unaffected. Even so, eMudhra is leaving the public TLS business rather than rebuild trust in its roots. Operators should check whether their certificates chain to an eMudhra root. Full details: report on eMudhra's exit and the technical write-up of CVE-2026-111943 for details.