low severity April 12, 2026 · 3 min read Unverified claim — what this is

Mytheresa Data Breach (2026)

If you are a customer of Mytheresa, here’s what is being claimed, and what it would mean for you.

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.

On April 12, 2026, luxury fashion retailer Mytheresa appeared on the leak site of the extortion group ShinyHunters after the company did not meet the ransom demand. The group released a dataset containing 84,000 unique email addresses along with names, phone numbers, physical addresses, purchase histories, salutations, and partial credit card details that included card type, last four digits, and expiry dates.

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Reported Details of the Breach

Public reporting from Have I Been Pwned confirms the incident involved 84K records and that the data first surfaced after the ransom deadline passed. The exposed information spans customer contact details, delivery addresses, order records, and limited payment card data. No full credit card numbers or CVV codes were included, which limits immediate financial fraud risk but does not eliminate longer-term identity exposure. The breach list entry attributes the leak directly to ShinyHunters’ “pay or leak” operation.

Why This Matters for You and Your Family

When your name, address, phone number, and email appear together with purchase history, criminals gain enough context to craft convincing phishing messages or impersonation attempts targeted at you or members of your household. Partial credit card data can be combined with other leaks to build a fuller profile that makes account takeover attempts more successful. For families, the exposure of children’s names or family addresses can open the door to harassment or social engineering aimed at younger users who may not yet recognize the risks.

Physical addresses and phone numbers are especially valuable because they allow attackers to cross-reference public records, people-search sites, and social media to map out where you live and who else shares that address.

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What the free scan actually returns

Sample resultyou@email.comIllustrative — not a real person

Found on people-search siteswe remove these

These listings are live, public, and legal to remove — and removing them is what we do.

value redacted in this sampleage, relatives, address historySpokeo

value redacted in this samplephone, household, property recordsBeenVerified

value redacted in this sample580 companies checked

Found in breach recordsverifiedreported — unverified

Each record is labeled: confirmed breach data, or an attacker’s claim no one has verified.

verifiedvalue redacted in this samplepassword + phone · 2024telecom breach

unverifiedvalue redacted in this sampleclaimed in ransomware listing · 2026leak-site claim

Leaked data cannot be deleted from the internet — anyone claiming otherwise is lying. Broker listings can be removed. We do the second, and show you exactly what to fix from the first.

Report details & sourcing

Attributed to ShinyHunters · 169 incidents tracked →

Severity Low includes account details that can be misused directly

Disclosed April 12, 2026

Last reviewed July 22, 2026

Affected 84K

Data exposed Email addressesNamesPartial credit card dataPhone numbersPhysical addressesPurchasesSalutations

By GalaxyWarden Threat Research · Editorial & sourcing standards

Unverified claim — what this report is

This page documents a public listing on a ransomware/extortion group’s leak site, tracked via public threat-intelligence sources. A listing is the attacker’s claim. GalaxyWarden aggregates and reports such claims; we have not independently verified that a breach occurred, what data (if any) was taken, or the accuracy of anything the group asserts, and the named organisation has not necessarily confirmed the incident. Sections above describe what the listing shows and the group’s documented history — not verified findings about the named organisation. If you represent this organisation and believe anything here is inaccurate, tell us and we’ll review it promptly.

Editorial & sourcing policy

GalaxyWarden is a breach-monitoring service and news aggregator. We do not exfiltrate, host, purchase, or redistribute stolen data. Breach information is compiled from publicly accessible sources and threat-intelligence platforms, and is reported as claims attributed to their source. We promptly correct or remove material shown to be inaccurate — see our content & takedown policy or write to support@galaxywarden.com.

Threat-actor tracker

ShinyHunters — 169 incidents tracked

Every breach we've attributed to ShinyHunters, in one running log. See who else they've hit →

Related breaches

high September 30, 2026