Data Breach at CSA Tax & Advisory: What You Need to Know
In a concerning development for clients of CSA Tax & Advisory, a licensed accounting firm based in Haverhill, Massachusetts, the firm has allegedly fallen victim to a data breach orchestrated by the notorious Lynx ransomware group. This breach compromises not only the firm’s internal security but also the sensitive personal data of its clients, raising serious concerns about identity theft and data protection.
About CSA Tax & Advisory
With over 75 years of experience, CSA Tax & Advisory (CSA) is a trusted name in personal financial planning, estate planning, and tax services for business owners and executives. Their commitment to client confidentiality and financial integrity has made them a reliable partner for many individuals and organizations in navigating the complexities of tax law and financial management.
What Happened?
On December 26, 2025, the Lynx ransomware group publicly claimed responsibility for the breach by adding CSA to its data leak site. According to the group, they have exfiltrated a variety of sensitive information that includes:
- Full names
- Social Security numbers (SSNs)
- Physical addresses
- Phone numbers
- Individual income tax returns (Form 1040)
- IRS e-file signature authorizations (Form 8879)
- Tax payment vouchers (Form 1040-V)
- Employer certification forms
- Internal corporate correspondence and financial records
This significant breach of client trust and data security poses serious risks for all affected parties, particularly concerning the potential for identity theft and financial fraud.
Next Steps
If you believe you may be impacted by this data breach or have concerns about your personal information, we encourage you to reach out to us at Srourian Law Firm (SLF). Our team is here to help you explore your options and take the necessary steps to protect your identity and financial well-being.
LINKS:

Srourian Law Firm is investigating a potential class action lawsuit against 🇺🇸 United States – CSA Tax & Advisory (CSA) for a recent data breach.
If you received a NOTICE OF DATA BREACH letter from 🇺🇸 United States – CSA Tax & Advisory (CSA), complete the form below so we can discuss your legal options.
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