eMudhra Hires KPMG to Review a Weak-Key Certificate Incident and Will Exit the Global SSL Business After Browsers Distrust Its Root

An Indian company whose business is built on digital trust has suffered a significant blow to that trust, and is now taking unusual steps to repair it.

eMudhra, the Bengaluru-headquartered provider of digital signatures and certificate services, has appointed KPMG as an independent external reviewer of a security incident involving weak cryptographic keys, the company announced on Friday, October 30, according to its incident statement and reports by APAC News Network. The company's board has also approved a voluntary withdrawal from the global SSL/TLS certificate business.

eMudhra's shares declined after the announcement, according to Kotak Neo.

What happened

On October 17, a security researcher reported to eMudhra and to browser trust programmes that keys belonging to eight intermediate certificate authorities (CAs) under one of eMudhra's elliptic curve cryptography (ECC) root certificates were weak, according to the company's statement. Mozilla received the report the same evening.

Certificate authorities issue the digital certificates that allow web browsers to verify that they are connecting to a genuine website, enabling the padlock symbol and encrypted connections. If a CA's keys can be recovered, an attacker could potentially issue fraudulent certificates that browsers would trust.

eMudhra revoked all eight intermediate CAs on October 18. Browser root programmes distrusted the associated ECC root as a precaution, and Chrome and Firefox blocked the affected TLS certificates, according to APAC News Network. Mozilla is removing the signing root from its NSS trust store.

The cause

The company said a flaw in a key wrap and unwrap step had produced a second, weak set of keys alongside the strong keys, and that the weak keys were published to browser root stores. The intermediates were created in a key generation ceremony on April 30, 2025, and the flaw went undetected for about 18 months, through two independent audit cycles.

"The flaw was ours. A script error resulted in issuing CA's with weak keys," eMudhra's leadership said in a note of apology.

Limited scope

eMudhra says the impact was limited. According to its statement, the revoked intermediates never issued any certificates, its infrastructure was not compromised and no data was breached. Only TLS certificates chaining to the distrusted ECC root were affected, limited to one US customer ecosystem of about 30,800 certificates. That ecosystem has been moved to an alternative RSA root pathway.

The company says its digital signature, eSign, emSigner, CertiNext, emCA, Privatrust and SecurePass products run on separate infrastructure and were unaffected.

Exiting the SSL business

eMudhra's board approved a voluntary withdrawal from the global SSL/TLS certificate business, citing rising compliance requirements, operational complexity and costs, and competition from free certificate providers such as Let's Encrypt, according to APAC News Network. Chairman V Srinivasan said the SSL/TLS business contributes about 1% of global revenue.

Most remaining TLS customers have already moved to alternative providers at no cost, and eMudhra has offered Sectigo-issued certificates as an alternative.

Why the KPMG review matters

The appointment of KPMG is intended to provide an independent assessment of the incident and of eMudhra's governance and compliance processes. For a company whose value depends on trust, an independent review can help reassure customers, regulators and investors.

eMudhra has also said it is reviewing its key generation ceremonies, offering CA redundancy to enterprise TLS customers and planning a full root-cause analysis through the Common CA Database (CCADB), the system used by browser root programmes.

The importance of certificate trust

Web browsers maintain lists of trusted root certificates, and CAs must meet strict requirements to be included. Browser makers have previously removed CAs that failed to meet standards, sometimes with severe consequences for the companies involved. The swift distrust of eMudhra's ECC root reflects the zero-tolerance approach browser programmes take to key compromise.

eMudhra's core business

eMudhra is one of India's largest certifying authorities for digital signatures, which are widely used for tax filings, company registrations, government tenders and digital agreements. Its eSign services allow Indian citizens to sign documents electronically using Aadhaar-based authentication. The company has expanded internationally, serving customers in the Middle East, Africa, Europe and the United States.

The company listed on Indian stock exchanges in 2022.

Lessons for the industry

The incident highlights the importance of rigorous processes in public key infrastructure, where a single error can undermine trust. It also illustrates how security researchers and browser programmes act as an important check on certificate authorities. For Indian technology companies seeking to compete globally in security and trust services, maintaining the highest standards is essential.

How certificate authorities work

Certificate authorities form a hierarchy of trust. At the top are root certificates, which are built into browsers and operating systems. Root CAs sign intermediate certificates, which in turn issue the certificates used by websites. Because root keys are so valuable, they are usually kept offline, and day-to-day issuance is done by intermediates. If an intermediate's keys are compromised, the intermediate can be revoked without replacing the root, but if browser programmes lose confidence in a CA's practices, they may distrust the root itself, as happened in this case.

Key generation ceremonies, in which CA keys are created under strict, audited procedures, are designed to ensure that keys are generated securely. eMudhra's incident shows how a flaw in such a process can go undetected despite audits.

Precedents

Browser programmes have previously distrusted certificate authorities over compliance failures. In 2017, Google and Mozilla moved to distrust Symantec's certificate business after finding repeated problems, a decision that led Symantec to sell the business to DigiCert. More recently, browser makers have distrusted other CAs over compliance concerns. These precedents show the high stakes for certificate authorities when trust is called into question.

What comes next

KPMG's review and the root-cause analysis will be closely watched by customers, browser programmes and investors. eMudhra's ability to demonstrate that the incident was isolated and that its core digital signature business remains secure will be key to restoring confidence. The company's exit from the SSL business will allow it to focus on its larger digital signature and identity businesses.

For customers of eMudhra's core products, the company's message is that their services remain secure, and the coming months will show whether that reassurance holds.

Industry experts say the episode will also prompt other certificate authorities to review their own key generation processes, potentially leading to stronger safeguards across the industry and reinforcing the importance of independent security research in keeping the internet's trust infrastructure secure.