India-based eMudhra Limited to Exit TLS Business Following Weak Encryption Scandal

India-based eMudhra Limited, a certificate authority responsible for issuing TLS credentials, has announced its decision to exit the business following a recent scandal involving weak encryption keys.

The company's chairman, V. Srinivasan, cited increasing costs and compliance requirements as major factors contributing to this decision. Additionally, the emergence of organizations offering free TLS certificates has reduced revenue from this segment, which accounts for only 1 percent of eMudhra's overall income.

eMudhra's exit from the TLS business is a significant development in the wake of researchers exposing eight defective intermediate certificates issued by the company. These certificates had private keys that were extremely vulnerable to exploitation, allowing anyone to generate trusted TLS certificates with minimal effort.

The ease with which these weak keys could be cracked has raised concerns about the potential consequences of their misuse. Researchers have warned that such vulnerabilities could be exploited to compromise email servers, IoT devices, and other systems relying on TLS certificates.

In a statement, eMudhra acknowledged that the intense media scrutiny surrounding this incident had contributed to its decision to withdraw from the global SSL/TLS market. The company's board has concluded that exiting the business is in the best interest of both eMudhra and its shareholders.

The compromised certificates issued by eMudhra had private keys that fell far short of industry standards. Normally, NIST P-384 elliptic curve cryptography keys are supposed to contain 384 bits of entropy, but these keys had much smaller sizes ranging from just 3 to 8 bits. This meant that the number of possible key combinations was severely limited, with the strongest of the defective keys having a maximum of only 256 possibilities.

The use of such weak keys raises serious concerns about data security and trust in online transactions. Browser makers were quick to act on this discovery, blocking certificates issued with intermediate certificates within just a day or two after they were found. This move was likely intended to prevent further potential breaches and protect users from potential harm.

eMudhra's certificate authority status was also at risk due to the severity of the issue. The CA/Browser Forum, an industry-wide group that sets rules for TLS certificate programs, could have pulled eMudhras' certification if they failed to address the problem promptly and effectively.

In response to the debacle, eMudhra provided a brief explanation for what went wrong. According to their statement, the compromised certificates were created during a Key Generation Ceremony (KGC) held on April 30, 2025, using FIPS 140-2 Level 3 Hardware Security Modules (HSMs). However, a flaw in the KGC process caused weak keys to be generated alongside strong ones.

eMudhra is now working to identify and rectify the root cause of this issue. The company's efforts will likely focus on ensuring that similar mistakes do not happen again in the future, given the severity of the consequences for users' trust and online security.

eMudhra's handling of encryption keys has raised serious concerns about the security and integrity of their operations.

The company's use of Hardware Security Modules (HSMs) is designed to safeguard sensitive data, including encryption keys. These dedicated devices are typically isolated from the rest of a network to prevent unauthorized access or leakage.

However, it appears that eMudhra deviated from standard procedures during the creation of ECC issuers on a specific day. A flaw in their Key Generation Certificate (KGC) script was identified, which led to the creation of weaker keys.

As part of their investigation, eMudhra reviewed their KGC and HSM key handling processes. They found that original ECC keys were created as expected, but an approved deviation from standard procedures was introduced for testing purposes. This deviation resulted in the creation of a second pair of keys, which were subsequently used by mistake to create a certificate signing request.

The weaker keys were then signed by eMudhra's root and sent to fellow certificate authority Sectigo for cross-signing. The company has verified that these files were indeed sent over to Sectigo.

The flawed key lifecycle integrity process has led to significant errors in the certificate revocation list (CRL) signatures. These CRLs were initially signed using private keys that were intended to produce correct signatures, but due to human error, they resulted in incorrect signatures.

As a result, these CRLs had to be resigned with flawed keys, further compromising their integrity. An investigation into the key ceremony process has revealed multiple human errors that contributed to this issue. The team is now scrutinizing code flaws and process gaps that may have contributed to this problem.

The use of flawed certificates raises concerns about the security of devices relying on these intermediate certificates. While browsers have blocked these certificates, other devices with longer update windows or those unable to block them altogether are still at risk.

Devices such as embedded systems may never be able to update their certificates, leaving them vulnerable to potential threats until they can be replaced or updated. The incident highlights the importance of rigorous key management and certificate revocation processes to ensure the security and integrity of digital communications.