Baker Tilly Advisory Group
How they got in, as reported. A supplier or vendor that was compromised first.
← All cases- Date
- 11 Nov 2026
- Place
- United States
- Who
- Baker Tilly Advisory Group · Accounting / CPA
- The way in
- Vendor compromise
- Source
- BleepingComputer
What was reported.
Baker Tilly is notifying clients that personal information about them and their dependents was exposed in a breach. The data was stored on a platform run by an unnamed third-party service provider, and the number of affected clients and data types were not disclosed.
The way in the source reports: a supplier or vendor that was compromised first.
The company said the exposed data was stored on a platform operated by a third-party service provider Baker Tilly uses to serve clients.BleepingComputer, added to these pages on 12 Nov 2026. The source
What a vendor compromise is.
A vendor compromise starts at a supplier. An attacker gets into a provider first and reaches its customers through the access or the trust the provider already has.
A message from a real supplier's real mailbox asking to change bank details is the common form. Software updated by a provider the attacker controls is another.
We read a supplier's own public mail records: whether forged mail in its name would be refused and whether look-alikes of its name are registered.
A reading of public records cannot see inside the supplier's systems. A changed bank detail is confirmed by a call to a number already on file, never by a reply.
This part is true of every case of this kind. It says nothing more about Baker Tilly Advisory Group than the source does.
What we check for it.
The outside services your domain depends on.
If this happens at your firm.
- Confirm every change of bank details on a number you already hold, even inside a real email thread.
- Agree with your main suppliers how a change of bank details is confirmed and keep it in writing.
What we read for accounting firms.
- The records that tell inboxes whether to refuse email sent as you (DMARC, SPF and DKIM), read externally.
- Web addresses an attacker could register to look like yours, each checked: is it registered, is it set up for mail.
- Breach records for addresses at your own domain, read externally; nothing inside is touched.
- The mail records of every other domain your firm owns, read externally.
- The certificate your website answers with, seen externally: its name, its dates and who issued it.
- Read with the assessment. What AI assistants answer about your firm. A client who asks an AI assistant about your firm trusts the answer it gives. Assistants build those answers from pages they crawl. A look-alike address an attacker could register can be built to be crawled: its robots file invites the AI crawlers in and its page claims your name. Attackers manipulate AI answers to send your paying and enquiring clients to their own look-alike page, web address, sign-in page, phone number or email. In 2025, asked for the sign-in pages of 50 brands, an AI assistant gave addresses the brand did not control one time in three. The check is built to ask six assistants: Claude, ChatGPT search, Gemini, Perplexity, Grok and Copilot, through Bing. Monitoring asks again every week and tells you when an impostor's phone or address is in an answer. Source: Netcraft research, read on 4 November 2026.
The rule, from its source: What does IRS Publication 4557 ask tax professionals to do?
See your own firm the way an attacker reads it.
We read your domain from public records and show each way in with a check anyone can re-run.
Source.
Source: BleepingComputer ↗This page repeats what the source reported, with its date. It says nothing about any firm that is not named in it.