Square Deploys Thales HSMs to Fight Cyber Attackers on its Own Terms

With a belief that everyone should have the opportunity to participate and thrive in the economy, San Franciscobased Square, Inc. is on a mission to build tools that make commerce easier and more accessible to all.

Square was founded in 2009, with offices in the United States, Canada, Japan, Australia, Ireland, and the UK. It offers sellers a broad range of payment acceptance options, complemented by reporting and analytics, next-day settlement, and chargeback protection. The company’s point-of-sale (POS) software and associated business services are designed to help sellers succeed. For example, significant innovation through the use of Square-designed readers for smartphones and tablets enables merchants to accept card payments in a secure manner without the complexity and cost of managing traditional fixed POS devices. The origin of the now substantial global mobile POS (mPOS) card acceptance market can legitimately be traced back to Square.

As with all companies, data integrity and the security of transactions are mission-critical factors. However, Square has a rather unique philosophy in the way it approaches its security architecture. Most attackers try to exfiltrate data so that they can work in the seclusion of their own systems. Square’s environment was architected from the very outset to prevent that from happening, incorporating hardware security modules (HSMs) as a required element.

Square Deploys Thales HSMs to Fight Cyber Attackers on its Own Terms

Business Challenge

The numerous regulatory bodies in Square’s sector dictated the need for the selected HSM to be compliant with a wide range of governmental and payment industry mandates that meet stringent security requirements. Square conforms to multiple standards, including the Payment Card Industry Data Security Standard (PCI DSS).

In addition to making reliability a primary objective, the Square team closely focused on the selection of any component in its architecture capable of compromising data integrity, performance or the seller experience.

Technical Challenge

The uniqueness and value proposition of Square’s offerings have made the company a resounding success and this has influenced the design criteria for the infrastructure. Square opted to handle scalability at the application layer and this created the need to be able to conveniently move keys between HSMs.

A key factor for selecting the optimal HSM for the Square implementation was a module’s ability to process vast amounts of data. Square profiled its software to understand how many authentication code operations and how many encryption calls were taking place, and replicated this to test HSM performance.


Square’s technical team performed a rigorous evaluation of multiple vendors and selected the Thales nShield Solo HSM because of its compelling performance across the full suite of tests. The Thales solution’s inherent ability to scale – enabled by the seamless sharing of keys across HSMs without user intervention or complex key cloning activities – was another of the many standout features.

The success of the Thales nShield Solo HSM in the cryptoanchor role has since paved the way for their use in injecting keys into Square’s readers to authenticate the devices. Every hardware product has its own unique key and the Thales products are a critical part of that process.


The fundamental value of the HSM-centric crypto-anchor approach has remained sound over an extended period of time. Several years since Square decided to use Thales nShield HSMs, the choice of Thales as a partner continues to hold valid.

The requirement to regularly conduct both internal and external audits can frequently be very labor-intensive and time consuming. However, the presence of the FIPS-certified Thales HSM can contribute to streamlining the process. During its DSS audit, for example, Square specifically highlighted that its data is protected by an encryption key, located in the Thales hardware security module. The inclusion adds to the volume of evidence provided to the auditors to demonstrate that any potential issues are being handled in a robust and compliant manner.

About Thales eSecurity

Thales eSecurity is a leader in advanced data security solutions and services that deliver trust wherever information is created, shared or stored. We ensure that the data belonging to companies and government entities is both secure and trusted in any environment – on-premises, in the cloud, in data centers or big data environments – without sacrificing business agility. Security doesn’t just reduce risk, it’s an enabler of the digital initiatives that now permeate our daily lives – digital money, e-identities, healthcare, connected cars and with the internet of things (IoT) even household devices. Thales provides everything an organization needs to protect and manage its data, identities and intellectual property and meet regulatory compliance – through encryption, advanced key management, tokenization, privileged user control and high assurance solutions. Security professionals around the globe rely on Thales to confidently accelerate their organization’s digital transformation. Thales eSecurity is part of Thales Group.