EY tax support breach exposes client financial data
An intruder accessed a third-party support platform used by EY's US tax practice from March 28 to April 12 and downloaded client documents containing personal and financial data. EY said the access was stopped. ShinyHunters later claimed the theft and threatened to publish the files, but its July 31 deadline passed without a confirmed public leak. EY has not confirmed the group's claim. A proposed class action lawsuit was filed against EY on July 28 over the breach.
- Started
- Mar 28, 2026
- Latest activity
- Jul 28, 2026
- Attributed to
- ShinyHuntersSuspected
- Where
- United States
- Sectors
- Finance
- Scale
- EY and an undisclosed number of clients
Current status
No credible post-August 5 report has documented an EY leak or official closure; separate reports dated August 28 and September 9 show ShinyHunters remained active against other victims.
Dormant: No new confirmed activity for a while, and nobody has called an official all clear.
Who is behind it
ShinyHunters claimed responsibility, but EY has not confirmed the link and no independent evidence has proved it.
Impact
The intruder downloaded support-ticket documents containing personal information and financial data used in tax filings. EY said on July 13 that it was not aware of misuse or further exposure. A proposed class action filed July 28 alleges EY failed to protect this data; the claims are unproven and there is nothing for affected people to file yet.
What to do
People who received an EY notice should use the offered monitoring, review financial accounts, and consider requesting an IRS identity protection PIN.
Timeline
-
Sep 11, 2026
No new confirmed activity reported, so this incident moved to dormant while it stays open.
Dormant -
Sep 9, 2026
GovInfoSecurity reported that ShinyHunters continued claiming attacks against other organizations, including Florida's DMV. No new EY activity or EY data leak was reported.
govinfosecurity.com -
Sep 8, 2026
BleepingComputer reported that ShinyHunters claimed a separate breach of Florida's DAVID DMV database. No connection to the EY incident was reported.
bleepingcomputer.com -
Aug 28, 2026
BleepingComputer reported that McKesson disclosed a separate incident after ShinyHunters claimed to have stolen patient data. No connection to the EY incident was reported.
bleepingcomputer.com -
Aug 5, 2026
A review found no public leak after ShinyHunters' July 31 deadline, while EY had not confirmed the group's claim or issued a closure notice.
Containedcloudskope.com -
Jul 28, 2026
EY was hit with a proposed class action lawsuit alleging it failed to protect client tax and financial data exposed in the breach.
Containedcfodive.com -
Jul 27, 2026
ShinyHunters claimed responsibility and threatened to publish the stolen files unless EY responded by July 31.
ransomware.live -
Jul 13, 2026
EY notified affected people, offered 24 months of identity monitoring, and said its systems were secure.
oag.ca.gov -
Apr 23, 2026
EY detected unusual activity and started its response, investigation, and recovery work.
oag.ca.gov -
Apr 12, 2026
EY's investigation found that the unauthorized access ended after documents belonging to several clients were downloaded.
Containedoag.ca.gov -
Mar 28, 2026
An unauthorized party began accessing the third-party support platform used by EY's tax practice.
Activeoag.ca.gov
Sources
- EY notice of data breach California Attorney General Jul 13, 2026
- Ernst & Young discloses data breach after support system hack BleepingComputer Jul 17, 2026
- Ernst & Young Data Breach Affects Personal, Financial Information SecurityWeek Jul 20, 2026
- Ernst & Young data breach claimed by ShinyHunters extortion gang BleepingComputer Jul 27, 2026
- ShinyHunters claim for Ernst & Young ransomware.live Jul 27, 2026
- ShinyHunters Claims Ernst & Young Data Breach, Threatens to Leak Stolen Data Security Affairs Jul 29, 2026
- EY hit with proposed class action over data breach Yahoo Finance Jul 27, 2026
- EY hit with proposed class action over data breach CFO Dive Jul 28, 2026 unverified
- EY Data Breach Hits Client Tax Info; Class Action Filed OpenClassActions Jul 28, 2026
- EY extortion deadline passes with third-party support-platform scope still unresolved Security.io Aug 3, 2026
- Three Breaches, Three Years. Client Tax Records in a Hacker's Hands. EY Still Won't Name the Platform That Failed. Cloudskope Aug 5, 2026
- McKesson discloses breach after ShinyHunters claims patient data theft BleepingComputer Aug 28, 2026
- ShinyHunters hackers claim breach of Florida DAVID DMV database BleepingComputer Sep 8, 2026
- Breach Roundup: ShinyHunters Claims Florida DMV Hack GovInfoSecurity Sep 9, 2026
Related reports
- ShinyHunters claims attack on Ernst & Young Jul 27, 2026
- EY breach threatens to expose client tax data Jul 27, 2026
- Ernst & Young Data Breach Affects Personal, Financial Information Jul 20, 2026
- EY data breach via hacked support system Jul 17, 2026
- Ernst & Young data breach by ShinyHunters ransomware gang Jul 8, 2026
- ShinyHunters threatens to leak EY tax data Jul 1, 2026
- EY tax client data leaked in IT support breach Jun 30, 2026