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Indian certificate authority eMudhra announced another major security remediation following its October cryptographic scandal. Specifically, the organization expanded the eMudhra certificate revocation to include eight additional RSA intermediate certificates. These compromised credentials originated from the exact same flawed generation workflow as the previously exposed ECDSA keys. Consequently, severe violations during private key handling forced administrators to invalidate the entire batch. Furthermore, the embattled vendor confirmed its permanent departure from the public TLS certificate market.
Flawed Migration Script Compromises Cryptographic Keys
Forensic investigations traced the root cause back to an infrastructure deployment on April 30, 2025. On that date, engineers generated sixteen intermediate certificate pairs across distinct regional facilities. To move keys between different hardware security modules, developers wrote a custom Python migration script. Although the hardware modules generated strong keys initially, the custom script corrupted the import process. Specifically, the software retained only the single leading byte when reconstructing ECDSA key objects. As a result, all eight ECDSA private keys held numeric values below 256, enabling trivial brute-force recovery.
Meanwhile, the eight accompanying RSA-4096 keys retained their full cryptographic bit length during the transfer. However, the script loaded raw private key material directly into unencrypted host Python process memory. This reckless exposure blatantly violated strict CA/Browser Forum standards governing private key protection. As detailed in the Mozilla Bugzilla incident analysis for eMudhra, these violations required immediate invalidation. Therefore, eMudhra revoked the RSA certificates under cessation of operation guidelines rather than explicit key compromise.
Missed Warning Signs During Early CRL Failures
Furthermore, post-incident audits revealed that warning signs surfaced as early as May and June 2025. During that period, several ECDSA intermediate certificates failed signature validation checks on their certificate revocation lists. Investigators discovered that the certificates referenced weak scripted keys while original hardware keys signed the lists. Instead of conducting a thorough root cause analysis, engineers simply swapped the signing key objects. Unfortunately, this superficial fix concealed the catastrophic single-byte private key flaw for months.
Permanent Exit from the Public TLS Market
Following severe reputational damage and low profit margins, eMudhra decided to abandon TLS certificate issuance entirely. Major web browsers already distrust the initial eight ECDSA certificates across modern desktop and mobile platforms. Nevertheless, unpatched command-line utilities and legacy firmware often ignore updated revocation lists. Consequently, outdated devices remain vulnerable to man-in-the-middle interception until administrators purge these roots manually. Ultimately, rigorous cryptographic auditing remains indispensable for maintaining global internet trust.
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