Breach date: 2026-05-23. Added to this index: 2026-06-03. Accounts affected: about 2.6M. Domain: dentaquest.com.
What happened
In May 2026, the dental benefits administrator DentaQuest was the target of a ShinyHunters "pay or leak" extortion campaign that resulted in the group publicly publishing hundreds of gigabytes of data allegedly obtained from the company. The data included 2.6M unique email addresses along with names, addresses and phone numbers. Much of the data appeared in healthcare enrollment files (ASC X12 transaction sets) with some containing Medicaid IDs, while additional data appeared in member records and related files. DentaQuest acknowledged "a cybersecurity incident involving unauthorized access to a limited portion of our network", and advised they had contained the attack and mitigated the threat.
Breach data sourced from Have I Been Pwned, used under CC BY 4.0. Additional breach metadata provided by XposedOrNot. DataExposed is an independent service and is not affiliated with or endorsed by either.
What was exposed
Dates of birth: Your full birth date, day, month and year, collected at signup for age checks, identity verification, insurance quotes, birthday offers or government services.
Email addresses: The email address you used to register or log in. It is the most common field in breaches because it doubles as your username on most sites.
Genders: The gender or sex recorded on your profile, usually picked from a list at signup, sometimes with a title such as Mr or Ms or a gender identity option beyond male and female.
Government issued IDs: Numbers or images of official identity documents, such as passports, national identity cards, Social Security numbers, Medicare cards, tax file numbers, residence permits and voter cards.
Health insurance information: Your health insurer, policy or member number, Medicare or national health card number, level of cover, claims history and sometimes the treatments and providers you claimed for.
Names: Your first name, surname and sometimes middle name or initials, as you gave them when you signed up. It appears in almost every breach because nearly every account asks for it.
Phone numbers: Your mobile or landline number, collected at signup for contact, delivery updates, marketing and two-factor codes.
Physical addresses: Your residential, postal, billing or delivery address, stored by retailers, utilities, banks, government services and almost any company that sends you something.
What to do now
Check whether your own address is in this dataset with the free email breach check.
Review the accounts connected to this service and turn on two-factor authentication.
Turn on two-factor authentication on your email account first, because it is the reset path for everything else.
Treat calls and messages that quote real details about you as hostile until you verify them another way.
Frequently asked questions
What data was leaked in the DentaQuest breach?
The DentaQuest breach exposed Dates of birth, Email addresses, Genders, Government issued IDs, Health insurance information, Names, Phone numbers, Physical addresses. About 2.6M accounts were affected.
Was I affected by the DentaQuest breach?
Run the free email breach check with the address you used on that service. It will tell you whether your address appears in this dataset.
What should I do about the DentaQuest breach?
Treat any message that quotes details from this breach as suspicious, turn on two-factor authentication, and consider removing your details from people-search sites if your address or phone was included.