What Is an HSM and How Does It Securely Store Private Keys?

Security Comes First in the Digital World

The rise in cyberattacks, the theft of personal data, and financial losses in recent years have clearly demonstrated that we need to take more measures to protect our digital assets. With the rise of cryptocurrencies, blockchain technologies, and other digital assets, the importance of digital keys has increased significantly. So, how can you protect the assets in your digital wallet? The answer is simple: Hardware Security Modules (HSMs). HSMs provide the strongest shield against cyberattacks by storing your digital keys on a physical device.

In this blog post, we’ll discuss what HSMs are, how they work, and why they’re important. We’ll also examine the HSM purchasing process, service providers, their role in storing private keys, and key considerations when acquiring this service. Additionally, we’ll evaluate a case study on HSM usage.

The topics covered in this article are as follows:

• What Is an HSM?

• What Is a Private Key? How Are HSMs Used to Store Private Keys?

• Why and How Do Organizations Need HSM Services?

• Why Is HSM Service Important for Cryptocurrency Exchanges?

• What Should Be Considered When Purchasing an HSM Service?

Case Study | AWS CloudHSM

What Is an HSM? An HSM (Hardware Security Module) is a specialized device used to secure sensitive data. These devices act like digital safes where critical information—such as your bank passwords and cryptocurrency wallets—is stored. So why use an HSM? It is used for digital signing to protect documents against forgery, data encryption to protect sensitive data from unauthorized access, and authentication to verify user identities. Simply put, an HSM is your safe in the digital world. It securely stores your valuable digital assets.

HSMs provide a secure environment for the generation, storage, and management of digital keys. This ensures that keys are generated, stored, and distributed securely. They are particularly capable of performing high-volume cryptographic operations quickly and efficiently for organizations with high transaction volumes, such as financial institutions and cryptocurrency exchanges. HSMs typically hold compliance certifications for international security standards such as FIPS 140–3 and Common Criteria, which demonstrate that they meet specific security requirements.

What Is a Private Key? How Are HSMs Used to Store Private Keys? A private key is a secret key used in cryptographic operations and plays a critical role in the processes of creating digital signatures, encryption, and decryption. In the world of cryptocurrency, private keys enable users to maintain control over their digital assets. Without these keys, it is impossible to send or spend cryptocurrency. A private key proves ownership of a digital wallet and prevents unauthorized access. If a private key is lost or falls into the wrong hands, access to the assets may be permanently lost.

In cryptocurrency systems, a private key is a secret code that ensures the security of digital wallets. It typically consists of long and complex alphanumeric sequences, making them difficult to guess or crack. In systems like Bitcoin, private keys are usually generated using the Elliptic Curve Digital Signature Algorithm (ECDSA). This key is required for transactions such as sending and spending cryptocurrency. Assets in the wallet are controlled by this key, and unauthorized access is prevented.

Cryptocurrency exchanges and wallet providers must offer various security protocols and tools to enable users to securely store their private keys. One such method is the use of HSMs.

HSMs also ensure that cryptographic operations are performed securely. For example, digital signature generation or encryption operations are performed within the HSM, and the private key never leaves the device during this process. For financial institutions and cryptocurrency exchanges with high security requirements, HSMs perform these operations at high speed and with high performance, thereby reducing transaction times.

Another advantage of using HSMs is that they meet regulatory and compliance requirements. Many financial regulatory agencies mandate the use of HSMs for the secure storage of digital keys. The fact that HSMs hold international security certifications such as FIPS 140–3 and Common Criteria makes them reliable and compliant with regulations.

HSMs offer numerous operational advantages regarding the storage and management of private keys. Thanks to centralized key management, large organizations can manage keys more efficiently. Automatic backup and recovery features ensure continuous access to keys. Additionally, HSMs play a critical role in multi-factor authentication systems by enabling secure user authentication processes.

Why and How Do Organizations Need HSM Services? HSMs are widely used across many sectors, including financial services, banking, cryptocurrency exchanges, government agencies, healthcare, and telecommunications. Banks and payment systems use HSMs to protect customer data and financial transactions. In cryptocurrency transactions, the secure storage and management of private keys are critical for exchange security and the protection of user assets.

Government agencies use HSM devices for national security and to protect citizen data. Healthcare organizations utilize HSM solutions to ensure the security of patient data, while telecommunications companies prefer these devices to protect customer data and communication information.

HSMs used for blockchain security feature capabilities such as key generation and storage, encryption, IP protection, signature verification, and isolated hardware memory. These specialized hardware components ensure data security and privacy, facilitate effective information management, and eliminate reliance on online storage.

Why Is the HSM Service Important for Cryptocurrency Exchanges? In 2020, the KuCoin cryptocurrency exchange suffered a cyberattack, and more than $280 million in assets were stolen. KuCoin CEO Johnny Lyu revealed that the attackers gained access to the private keys associated with the exchange’s hot wallets. KuCoin transferred the remaining assets to new hot wallets, disabled the old wallets, and suspended deposit and withdrawal transactions. Although user losses were covered by an insurance fund, this incident led to a loss of user trust.

As seen in the example above, HSM services are vital for cryptocurrency exchanges because the secure storage of digital assets directly impacts the exchange’s operational security and customer trust.

Cryptocurrency exchanges process high-volume, high-value transactions every day. To ensure these transactions are conducted securely, private keys must be stored in a secure environment that is inaccessible from the outside. HSMs store private keys in a physically isolated environment, making external access virtually impossible.

Additionally, exchanges may be subject to security and compliance standards set by regulatory agencies. HSMs play a key role in meeting these requirements thanks to international security certifications such as FIPS 140–3 and Common Criteria. This compliance demonstrates that the exchange meets legal requirements and provides a secure service.

User trust is a critical factor for cryptocurrency exchanges. Users want to be certain that their assets are secure. The robust security measures implemented by exchanges reinforce this trust. The use of HSMs enhances the exchange’s reliability and protects user assets.

From a user experience perspective, fast and instant transactions are of great importance. HSMs execute these transactions at high speed and with reliability. This positively impacts the user experience and increases the exchange’s operational efficiency.

What Should Be Considered When Purchasing an HSM Service? There are several critical factors to consider when purchasing an HSM service:

Certification: First, verify whether the HSM provider holds security certifications. Certifications such as FIPS 140–3 and Common Criteria demonstrate that HSMs comply with international security standards.

Infrastructure Compatibility: Compatibility with the existing infrastructure is crucial. The HSM’s ability to integrate seamlessly with existing software and hardware reduces technical issues and streamlines the process.

Technical Support and Maintenance: It is critical for long-term performance that the service provider offers professional support for installation, management, and maintenance, and provides rapid solutions to issues.

Scalability: Business needs may change over time. The HSM must be able to adapt to these changes and scale easily.

Security Features: The device must minimize the risk of data loss through features such as backup and recovery, and ensure continuous access.

Cost: The total cost of the HSM service, including maintenance and support expenses, must be evaluated alongside the benefits it provides. Long-term returns and the reduction of organizational risks play a significant role in this decision.

Selecting the right HSM provider is critical for long-term security and operational success. In this context, Vinu’s HSM solutions offer a key management model that covers all processes—from the generation and storage of private keys to their secure use.

Case Study | AWS CloudHSM In a project conducted with a cryptocurrency exchange, a module was created and managed using HSM to ensure the security of private keys. By integrating HSM solutions into this project, user assets were securely stored and transactions were executed reliably.

1. Project Kickoff and Requirements Analysis: At the start of the project, a comprehensive requirements analysis was conducted to ensure the security of private keys. The analysis concluded that private keys must be generated within HSMs and stored in a physically isolated environment.

2. Integration Process: During the module development process, the AWS infrastructure and HSMs were used together. AWS CloudHSM was selected due to its high security standards and scalable architecture.

3. Security and Performance: One of the greatest advantages of HSMs is that private keys never leave the device. All cryptographic operations were performed within the HSM. This ensured the security of transactions and the protection of user assets. Thanks to high performance, transactions were executed quickly and seamlessly.

4. Regulatory Compliance: During the project, it became evident that the use of HSMs provided significant benefits in terms of regulatory compliance. AWS CloudHSM’s certifications, such as FIPS 140–3, contributed to ensuring legal compliance.

5. Our Expert Team: The team consists of cryptography experts, software engineers, and security analysts. They played an active role in all processes, from design to implementation. The flexibility offered by the AWS infrastructure enabled the team to work quickly and efficiently.

6. Results: The use of HSMs in this cryptocurrency exchange project provided an ideal solution for ensuring private key security and executing transactions securely. The high security, performance, and compliance advantages offered by HSMs provided significant benefits in protecting user assets and ensuring regulatory compliance. This infrastructure helped the exchange gain user trust.

AWS CloudHSM Performance: Scalability and Testing Recommendations

The performance of AWS CloudHSM clusters may vary depending on specific workloads. You can add additional HSM instances to your clusters to improve performance. However, performance may vary based on configuration, data size, and the application load on your EC2 instances. Therefore, it is recommended to perform load testing to determine your application’s scaling requirements.

The table below shows approximate performance values for common cryptographic algorithms running on an EC2 instance of the hsm1.medium type. Ensure that your HSM service operates within the limits specified below.

• In a cluster with two HSMs, a Java multithreaded application runs on a single c4.large EC2 instance and is located in the same availability zone as the HSM EC2 instance.

• In a cluster with three HSMs, the Java multithreaded application runs on a single c4.large EC2 instance and is located in the same availability zone as an HSM EC2 instance.

• In a cluster with six HSMs, the Java multithreaded application runs on a single c4.large EC2 instance and is located in the same availability zone as two HSM EC2 instances.

At Vinu, you can contact us to learn more about our HSM services, find the solutions best suited to your needs, and ensure the security of your digital assets. Our team of experts is here to guide you in developing and implementing custom HSM solutions. We’re always ready to answer your questions about our HSM solutions, evaluate your demo requests, and provide you with the best possible service.