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eMudhra, an Indian certificate authority (CA), has announced that it will exit its global SSL/TLS certificate business due to concerns over the vulnerability of its intermediate CA certificates. The move comes after a researcher discovered that the private keys of eight of eMudhra's intermediate CA certificates could be easily guessed, rendering the certificates insecure. The company will replace affected customers' certificates with free ones from partners, but has not specified when the exit will occur. The incident has raised questions over eMudhra's transparency and incident handling during and after the 2025 incident.
eMudhra is withdrawing from its global SSL/TLS certificate business due to vulnerability concerns. A researcher discovered that eight intermediate CA certificates could be easily guessed, rendering them insecure. Chrome and Firefox will stop trusting the eMudhra root certificate above the affected intermediates. About 30,800 unexpired certificates are affected, with 99.9% issued through InCommon. eMudhra will replace affected certificates with free ones from partners. The incident has raised concerns over eMudhra's transparency and incident handling. The company has stated it will continue to serve customers using its G1 RSA root certificates. The global SSL/TLS business brings in about 1% of eMudhra's revenue.
eMudhra, an Indian certificate authority (CA), has made the decision to withdraw from its global SSL/TLS certificate business, citing concerns over the vulnerability of its intermediate CA certificates. The move comes after a researcher discovered that the private keys of eight of eMudhra's intermediate CA certificates could be easily guessed, rendering the certificates insecure. According to eMudhra, the decision to exit the global SSL/TLS business was made by its board, five days after the researcher reported the vulnerability.
The vulnerability was first reported by the researcher on October 17, and Chrome and Firefox blocked the six TLS intermediates within hours. The researcher found that the private keys of the eight intermediate CA certificates were below 256, making them easily guessable. eMudhra stated that it never used the eight intermediates to issue certificates to websites or users, and that its systems were not breached.
As a result of the vulnerability, Chrome and Firefox will stop trusting the eMudhra root certificate above the affected intermediates. The change is expected to reach users on the morning of October 27, Pacific time. According to eMudhra, about 30,800 unexpired certificates chained to the affected root as of October 21, by Chrome's count. Of those, 99.9% were issued through InCommon, the certificate service Internet2 created for the higher education community.
eMudhra has estimated that about 30,000 certificates need to be moved, and that about 97% of them were issued using ACME, the protocol many servers use to request and renew certificates automatically. The company has announced that it will replace affected customers' certificates with free ones from partners, although it did not name the partners or provide a date for the exit.
The incident has also raised concerns over eMudhra's transparency and incident handling during and after the 2025 incident. In 2025, eMudhra published invalid CRLs for six of the same intermediates, and Chrome has asked why the 2025 report did not mention that two key pairs existed for each of those CAs. eMudhra has stated that it will continue to serve customers using its G1 RSA root certificates, which will continue to serve customers until the transition is complete.
The global SSL/TLS business brings in about 1% of eMudhra's revenue, and data sovereignty and compliance rules make it more complex and costly to run. Some large providers give the certificates away free. The incident's spread on social media has also brought "scrutiny that is out of proportion to SSL/TLS’s place in our business," the company said.
The researcher reported the weak keys to Apple, Google, Microsoft, Mozilla, and eMudhra on October 17. Each private key should have been a huge random number, but all eight were below 256, so anyone could work them out almost instantly. Chrome and Firefox blocked the six TLS intermediates within hours. No website certificate from them had appeared in CT logs before Chrome's block, so none could have been used against Chrome or other software that requires CT logging, Google said.
InCommon moved the service onto eMudhra's CertiNext platform between April and July this year. Google has told website operators with certificates under that root that they "must immediately acquire and install a new TLS certificate from another PKI hierarchy included in the Chrome Root Store."
The University of Michigan says InCommon's RSA certificates are not currently affected, but that their root "could become distrusted, too." For now, its main alternative is Let's Encrypt. Cornell has told its certificate holders to request RSA certificates instead of ECC ones, because "RSA certificates use eMudhra's unaffected root and should work." The university counts more than 300 affected certificates of its own.
eMudhra has estimated that about 30,000 certificates need to be moved, and that about 97% of them were issued using ACME, the protocol many servers use to request and renew certificates automatically. Chrome has told eMudhra that standard ACME clients do not replace certificates outside their renewal window unless they support ACME Renewal Information (ARI) or someone steps in by hand. Moving from the ECC hierarchy to the RSA one may also need changes to client settings.
The incident has also raised questions over eMudhra's RSA root. Mozilla said on October 20 that, for now, it was not removing trust in the G1 root, emSign Root CA - G1. At Stanford, InCommon certificates chain to that root through an eMudhra CA called emSign Root TLS CA - G1.
On October 14, eMudhra published a certificate revocation list (CRL) for emSign Root TLS CA - G1. A CRL is the signed list of certificates a CA has revoked. This one's signature does not verify against that CA's own key, the researcher who reported the weak keys said in Mozilla's public bug report on the incident.
A participant in the same bug report said on October 22 that the list appears to have been signed with the key of an eMudhra OCSP certificate. OCSP certificates sign answers about whether a certificate has been revoked. The participant wrote that the match "appears to be a case of using the wrong signing key, rather than evidence of another weak key."
Chrome raised the list on October 21, in one of 12 questions it posted to the bug report. It asked which key signed it, and whether eMudhra holds more than one key pair for that CA or for any of its roots.
Chrome also asked whether customers are moving to G1, to another company's CA, or both, and when all of them will have moved, given its planned October 27 removal. eMudhra said on October 20 that G1 was "the only alternative available," and the next day that it is issuing its affected US customers fresh certificates "from an alternate, independently operated, publicly trusted CA hierarchy."
In 2025, eMudhra published invalid CRLs for six of the same intermediates. Its incident report at the time said it fixed them by "regenerating the CRLs using the appropriate private key associated with each Intermediate CA."
On October 19, eMudhra told Mozilla that those lists were first signed with the keys it meant to use. When that produced invalid signatures, they were "resigned with flawed keys," the weak keys found this month.
Related Information:
https://www.ethicalhackingnews.com/articles/eMudhra-to-Exit-Global-SSLTLS-Business-Amid-Vulnerability-Concerns-ehn.shtml
https://thehackernews.com/2026/10/emudhra-to-exit-global-ssltls-business.html
Published: Thu Oct 22 13:40:51 2026 by llama3.2 3B Q4_K_M
