New Delhi:
Eight weak private keys operated by eMudhra were found to be vulnerable to near-instant recovery, prompting Google and Mozilla to block the affected certificates and raising questions about security audits and regulatory oversight.
Experts say the incident exposes weaknesses in the digital trust infrastructure that underpins website authentication, with concerns over how the keys were generated, why the flaw went undetected and whether systems beyond web browsers remain exposed.
While the incident creates a risk of fraudulent certificates, website impersonation and potentially intercepted communications, there is no publicly confirmed evidence that the keys were exploited by attackers or that any data breach occurred.
Experts have also called for greater accountability from eMudhra and the Controller of Certifying Authorities (CCA), which receives the company's audit reports.
The incident relates to eMudhra's international certificate business, which issues digital certificates trusted by browsers and operating systems to authenticate websites and software.
The government has said the company's Digital Signature Certificate (DSC) and eSign services regulated by the CCA remain unaffected.
Questions Over Audits And Oversight
Apar Gupta, founder of the Internet Freedom Foundation (IFF), said eMudhra had put a private key with the value 4 into service and, when its revocation lists produced invalid signatures in May 2025, re-signed them using the same weak keys.
"That is negligence in the one duty a certifying authority exists to perform," Gupta said.
He questioned how the flaw persisted for 18 months despite what eMudhra described as two years of independent audits. Gupta said the CCA, which receives eMudhra's audit reports every year, must tell the public what it reviewed.
The incident raises questions about whether audits adequately examined the generation, handling and use of private keys, and whether existing safeguards were effective in detecting vulnerabilities in certificate infrastructure.
Cybersecurity Policy And Regulatory Response
Ramanjit Singh Chima, programme director at the Association for Progressive Communications (APC), said the incident raised concerns about the integrity and effectiveness of certifying authorities and the state of India's cybersecurity policy.
"It is positive that CERT acknowledged the compromise. The integrity and effectiveness of certifying authorities are at stake. India is facing past certificate compromises, and trust status decisions by Google and Mozilla," Chima said.
He also pointed to longstanding concerns about the lack of a consolidated cybersecurity policy.
"Thirteen years ago, warnings were given about the government acting in a manner that showed India did not have a clear, consolidated cybersecurity policy. It was indicated that India would have a strategy, but that has not happened. There is a need to urgently address the economic and national security risks," he said.
No Confirmed Data Leak, But Misuse Was Possible
Jyoti Panday, a doctoral researcher at the University of Stavanger, said the incident should be understood primarily as a compromise of cryptographic keys that could allow certificate misuse, rather than treated as evidence of a confirmed data leak.
"If an intermediate CA's private key is generated with insufficient randomness-for example, using a small, predictable number instead of a securely generated cryptographic key-an attacker may be able to recover the private key and misuse the CA's signing authority," she said.
Such access could allow an attacker to issue fraudulent certificates for legitimate websites, impersonate domains or potentially facilitate man-in-the-middle attacks under certain conditions. However, more evidence would be needed to establish that attackers intercepted communications, accessed sensitive information or extracted data.
Panday said exploitation was technically possible from the time the affected keys were created in April 2025, but there was no confirmed public evidence that attackers had used them during that period. The date of key creation does not establish that an attacker had discovered or exploited the weakness at the time.
A weak certificate authority private key would not, by itself, give an attacker access to a website's server, databases or stored customer records. Intercepting communications would also depend on other conditions, including an opportunity to intercept network traffic and whether the client accepted the fraudulent certificate.
Risks Beyond Web Browsers
Panday said browser-level blocking does not necessarily protect all systems that rely on digital certificates. Business servers, embedded devices, cloud workloads and other software may use separate trust stores or may not receive automatic security updates.
"Organisations must identify affected components and update the relevant software and trust stores rather than assuming browser-level blocking protects their entire infrastructure," she said.
She also said it was not clear what action industry and state actors in India had taken to secure government portals, law-enforcement domains and other systems, or whether any remained exposed.
The distinction between eMudhra's international certificate business and its domestic services remains important. The reported compromise of international TLS intermediate certificates does not, by itself, establish that Indian tax-filing systems, GST services or domestic digital-signature credentials have been compromised.
Government Response
The Ministry of Electronics and Information Technology (MeitY) has said it took serious note of the incident and formed a special team to examine it. The government said the impact on Indian websites and applications was "very limited and for a very short interval".
It distinguished between eMudhra's two areas of activity: DSC and eSign services regulated by the CCA, and its international business supplying certificates trusted by browsers. The government said the reported incident concerned the latter and that the CCA-regulated DSC and eSign services remained unaffected.
The Indian Computer Emergency Response Team (CERT-In) issued an advisory on the incident. The government said further details would be shared after the investigation.
The incident has put the focus on how the weak keys were generated and deployed, how the problem escaped detection and what eMudhra's audits and regulatory reviews covered. It has also raised questions about whether blocking affected certificates in major browsers is sufficient to address the risks across the wider digital ecosystem.
The investigation and any independent assessment of the company's security processes will be key to establishing the full extent of the compromise, whether there was any exploitation and what measures are needed to prevent a recurrence.