Search Encrypted: Unlocking Secure Data Search Without Compromising Privacy

Key Takeaways:

• Searchable encryption allows you to securely search over encrypted data without compromising data privacy.
• Traditional methods of decrypting data for search purposes pose security risks and are not practical for sensitive information.
• Field-level encryption and application-level encryption provide some level of security but fall short of enabling true search through encrypted data.
• Searchable encryption utilizes blind indexes and strong ciphers to enable secure search operations without exposing decrypted data.
• Choosing whether to implement searchable encryption depends on the specific risks, threats, and performance requirements of your system.

Introduction

Data security is paramount in today’s digital landscape, where sensitive information is stored, transmitted, and processed on a massive scale. One challenge that organizations face is finding a balance between encrypting data to protect privacy and being able to search and retrieve specific information without compromising security. In this article, we explore the concept of “search encrypted” or searchable encryption, which allows for secure searching over encrypted data. We will delve into different approaches and highlight the benefits and considerations associated with this technique.

The Challenge: Balancing Data Privacy and Searchability

To understand the need for searchable encryption, let’s consider a scenario where valuable encrypted data, such as personally identifiable information (PII) and financial data, is stored in a database. An application backend interacts with the database, performing read and write operations, while a client app utilizes the data. The challenge arises when the client app needs to search for specific data without decrypting it on either the database side or the app backend side.

Traditionally, several approaches have been used, but they have limitations in terms of security and practicality. Let’s explore some of these approaches before diving into searchable encryption.

Traditional Approaches: Limitations and Insecurity

Local Database Download and Decryption

One basic approach is to download the entire encrypted database, decrypt it locally, and then search for the desired results. While this method may work in some cases, it is non-practical, insecure, and does not truly qualify as “search through encrypted data.”

Data-at-Rest Encryption

With data-at-rest encryption, data is stored in an encrypted form on disk but is decrypted in memory when accessed by an application. Although the data may be sent back to the app using Transport Layer Security (TLS), it is not truly searchable in an encrypted state. Once again, this method falls short of the goal of secure data search.

Field-Level Encryption: Application-Level Encryption

Field-level encryption involves encrypting data fields before storing them in the database. While this method offers a higher level of security, it still requires the application (backend or mobile) to handle the encryption and decryption processes. This approach, known as application-level encryption, does not fully enable search through encrypted data.

Introducing Searchable Encryption

To address the limitations of traditional approaches, searchable encryption offers a solution that allows data to remain encrypted while enabling efficient search operations. Searchable encryption ensures that neither the database server nor the app backend sees the decrypted data, enhancing privacy and security.

But how does searchable encryption work? It relies on special encryption ciphers or combinations thereof to achieve the desired outcome. One emerging technique is Fully Homomorphic Encryption (FHE), although experts often caution against its current readiness for production usage.

Another approach is to employ a “blind index.” This method utilizes strong, industry-proven ciphers like AES-GCM to encrypt the data fields. However, before storing the encrypted data, a “searchable hash” or blind index is calculated from the original field. The database then stores both the hash and the encrypted value of the field. When a search is required, the backend application calculates a blind index for the search query and executes a database command to compare the indexes. This approach is particularly effective when working with SQL databases.

Is Searchable Encryption a Silver Bullet?

While searchable encryption offers an exciting solution, it is important to note that there is no one-size-fits-all security solution. The applicability of searchable encryption depends on the risks and threats specific to your system. In some cases, it may be more suitable to keep encrypted data as-is, without enabling search functionality.

When considering whether to implement searchable encryption, it is crucial to make informed choices based on your system’s demands for performance efficiency and the required speed of secure search schemes.

Conclusion

Searchable encryption provides a promising avenue for securely searching over encrypted data, striking a balance between data privacy and searchability. By utilizing blind indexes and strong encryption ciphers, organizations can enable secure search operations without exposing decrypted data to potential vulnerabilities. However, it is essential to evaluate the risks and requirements of your system before implementing searchable encryption, as there is no one-size-fits-all solution in the realm of data security.

In today’s data-driven world, protecting sensitive and valuable data is of utmost importance. Whether you choose to leverage searchable encryption or explore alternative methods, partnering with trusted experts in data security, such as Cossack Labs, can provide invaluable guidance and support in safeguarding your organization’s critical information. Embrace the power of search encrypted and unlock the potential of secure data search without compromising privacy.