If your company stores sensitive client data or relies on third-party vendors for file transfer, the Eisner Advisory Group LLC data breach is worth your full attention.
This incident isn’t just about one accounting firm in New York. It’s a warning sign for every business that handles financial, legal, or healthcare information. Here’s a breakdown of what happened, what it means for organizations like yours, and what you should be doing now to avoid being next.
What Happened in the Eisner Advisory Group LLC Data Breach?
In September 2023, Eisner Advisory Group LLC—a major U.S.-based accounting and consulting firm—detected suspicious activity in its systems. The company launched a forensic investigation, and what they found was serious. Between September 4 and 9, attackers accessed files containing personal data.
Here’s the part that caught attention: clients weren’t notified until April 2025.
That delay triggered legal scrutiny and raised questions about how long the data had been exposed. As of now, the firm has acknowledged that names, Social Security numbers, driver’s license and passport details, financial records, and even health insurance information may have been accessed.
While the firm did act—by shutting down the affected systems, hiring forensic experts, and notifying authorities—the delay in notification left clients exposed for nearly 19 months.
Who Was Affected?
Eisner Advisory Group LLC provides services to businesses, high-net-worth individuals, and family offices. The breach affected thousands of records, including clients from its tax, estate planning, and business advisory units.
If you’ve worked with any Eisner Advisory Group LLC locations in recent years, particularly their flagship office at Eisner Advisory Group LLC / New York, your information may be at risk.
According to filings submitted to state regulators, the compromised data includes:
- Full names
- Social Security numbers
- Government ID (license or passport)
- Medical and insurance details
- Bank account or payment card information
The company stated that not all individuals had all types of data exposed. But even partial exposure can be enough for fraud or identity theft.
Why the Delay in Notification?
That’s the question a lot of people are asking.
The breach was detected in September 2023, yet affected individuals weren’t notified until April 8, 2025. There’s no clear answer from the company, but legal experts are pointing to the possibility of prolonged investigations, internal approvals, and delayed regulatory triggers.
Regardless of reason, this gap created more risk. Hackers often sell or trade stolen information within weeks. By the time clients knew, their data could have been circulated across multiple networks.
Legal and Financial Fallout
Multiple law firms have opened investigations. Murphy Law Firm, Federman & Sherwood, and others are exploring class-action lawsuits. Their main focus: Was the delay in notification negligent? Could it have worsened harm to affected clients?
So far, Eisner has offered affected parties credit monitoring and identity theft protection. But legal analysts expect more to come.
Can you sue after a breach like this? Possibly.
If you suffered documented financial loss, fraud, or had to deal with account closures, you may have a claim. Each case is different, but businesses and individuals impacted by the Eisner Advisory LLC data breach should consult counsel.
What Businesses Should Learn From This?
If you’re in B2B, handle client data, or rely on third-party file sharing platforms, the Eisner breach is a playbook in what not to ignore.
First: third-party risk is real. The initial breach came through MOVEit—a file transfer tool trusted across industries.
Second: VPN access restrictions could have made it harder for attackers to move laterally. Had the stolen data been behind a VPN with MFA and IP restrictions, the impact may have been contained.
Third: fast response matters. Waiting 19 months to alert users is unacceptable.
What To Do If You’re a Client?
- Enroll in the credit monitoring services provided.
- Place a fraud alert with a major credit bureau (Experian, Equifax, or TransUnion).
- Monitor financial statements and insurance activity closely.
- Get an IRS Identity Protection PIN to prevent tax return fraud.
- Contact Eisner Advisory Group LLC through the official Eisner Advisory Group LLC phone number if you haven’t received a letter but suspect exposure.
How PureVPN White Label Can Help Businesses Respond Better?
A common thread in modern breaches? Weak access control.
PureVPN’s White Label VPN solution gives businesses full control over remote access. You can limit entry by device, IP, and location. Admin panels let you see which users are accessing which systems and from where.
This kind of visibility helps:
- Detect abnormal logins
- Prevent credential abuse
- Keep sensitive data behind secure layers
If Eisner had implemented stricter access layers via VPN-only gateways, the breach might have stopped at the edge.
That’s what PureVPN White Label helps deliver—secure, scalable, brandable access management built for modern businesses.