eMudhra has revoked eight additional intermediate certificate authority (CA) certificates after an investigation found that a custom Python script handled their RSA private-key material in the memory of a computer outside the hardware security modules meant to protect it. The November 7 revocations bring the total number of affected intermediate CAs in the incident to 16.
In the full incident report filed in Mozilla’s Bugzilla tracker, eMudhra said the RSA-4096 keys retained their cryptographic integrity: signatures still verify against the certified public keys. However, the same read-and-recreate process used for the earlier ECDSA keys placed RSA private-key components in the volatile memory of the ceremony computer. The company therefore could not demonstrate that the handling met its certificate practice statement’s requirements for transferring private keys into or out of a hardware security module. It revoked the eight RSA intermediates with a cessation-of-operation reason code, not a key-compromise code.
The additional certificates comprise six TLS intermediates and two code-signing intermediates. Four RSA G2C issuers were put into production and issued 195 end-entity certificates, including 29 for eMudhra’s own domains. The affected certificate holders have been moved to replacement certificates, according to the report and The Hacker News’s original reporting. The last end-entity certificate issued by EM OV TLS CA – G2C was dated November 3, after which issuance from the G2C issuers stopped.
The earlier October incident involved eight ECDSA intermediates whose private values were truncated to a single leading byte by the same script, making their keys recoverable from public certificates. eMudhra revoked those certificates on October 18. The company also identified a June 2025 certificate-revocation-list signing problem as an earlier warning sign of the process failure. The first wave of revocations also prompted Microsoft’s emergency Windows updates for the affected certificate chains after the disclosure of eight compromised eMudhra TLS certificates.
eMudhra said the cross-vendor key-transfer process was a one-off and that its other key ceremonies generated keys in place. The company is exiting publicly trusted TLS certificate issuance, and its published phase-out schedule says all issuance from its remaining G1 hierarchy will stop before November 16, with Apple set to remove that hierarchy on November 30. KPMG’s independent review is due by December 4. eMudhra says it knows of no misuse of the RSA keys. The report’s unresolved question about software that does not enforce Certificate Transparency concerns the earlier ECDSA keys, not the newly revoked RSA intermediates.
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