Preventing Industry Contagion

APIs and data flows connect us all. One vulnerable organization can compromise the entire ecosystem.

The Contagion Effect

Quick and dangerous spread

A security incident at one CPA organization can quickly spread:

  • Upstream to technology providers and service partners
  • Downstream to clients and their employees
  • Laterally to integrated service providers

This inter-connectedness means that the industry is only as strong as its most vulnerable participant.

Our approach to industry-wide protection

HCM Defender implements a multi-layered strategy to prevent the spread of cyber threats:

  • Unified Standards: We establish baseline security standards that address the specific needs of the CPA ecosystem, creating a consistent security foundation across member organizations.

  • Connection Security: We develop protocols and best practices for securing API connections, data transfers, and integrations between CPA service providers.

  • Collective Defense: Our members benefit from shared threat intelligence, allowing the entire industry to respond quickly to emerging threats before they can spread.

Strength through collaboration

The CPA profession operates in one of the most digitally entangled ecosystems in business, where tax, audit, advisory, and e‑filing platforms exchange sensitive data across firms, clients, and regulators every day.

Did you know?

  • More than 85% of top CPA firms rely on five or more software point solutions to manage their tax workflow
  • 93.3% of individual tax returns were filed electronically in FY 2024, funneling taxpayer data through the IRS e‑file system
  • 66% of firms already conduct most of their business digitally, and that share is expected to reach 84% within three years

The consequences

  • A vulnerability in a single shared tax application can cascade to every interconnected firm, exposing client SSNs and financial records
  • Constant data hand‑offs—from client portals to cloud hosts to federal and state agencies—create multiple exposure points outside the firm’s direct control
  • Compromised credentials allow ransomware operators to move laterally through integrated bookkeeping, tax, and payroll systems, crippling operations during filing season

The Value of Participation

By joining CPA Defender, your organization becomes part of the solution to industry-wide security challenges. Your participation strengthens not only your own security posture but contributes to the resilience of the entire CPA ecosystem.