Mytheresa data breach: 84K accounts exposed
Severity: high · Patch status: no-fix-needed · Since 2026-05-27
In April 2026, the luxury fashion e-commerce platform Mytheresa was listed as a victim of the ShinyHunters "pay or leak" extortion group. After the ransom deadline passed, the group publicly released the data which contained 84k unique email addresses. The exposed data also included names, phone numbers, physical addresses, purchases and partial credit card data including card type, last 4 digits and expiry date. Exposed data: email addresses, names, partial credit card data, phone numbers, physical addresses, purchases, salutations. The breach dates from Apr 12, 2026; Have I Been Pwned loaded it on May 27, 2026.
What to do
- If you had a Mytheresa account, change its password and the password of any other account that reused it.
- Turn on multi-factor authentication wherever it is offered.
- Check whether your addresses are in this breach at https://haveibeenpwned.com.
- Expect targeted phishing that quotes the leaked details; verify any unexpected contact out of band.
Sources
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