[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$f1cljma9rz48ei":3},{"success":4,"breach":5},true,{"_id":6,"name":7,"title":8,"slug":9,"domain":10,"breachDate":11,"addedDate":12,"modifiedDate":13,"contentUpdatedAt":14,"source":15,"sourceUrl":16,"sourceUrls":17,"pwnCount":18,"affectedCount":18,"affectedCountStatus":19,"affectedCountLowerBound":20,"affectedCountUnit":21,"hasEnglishDescription":4,"severity":22,"dataClasses":23,"description":28,"seoTitle":16,"seoTitleEn":29,"seoDescription":16,"seoDescriptionEn":30,"logoUrl":31,"isVerified":4,"isSensitive":4,"isSpamList":32,"isMalware":32,"company":33},"68e3266eda11adda488253d4","troy-hunt-mailchimp-list","Troy Hunt's Mailchimp List Data Breach","troy-hunts-mailchimp-list","troyhunt.com","2025-03-25T00:00:00.000Z","2025-03-25T13:45:48.000Z","2025-03-29T09:51:58.000Z","2026-07-18T23:59:56.521Z","Third party breach","",[],16627,"known",null,"unknown","Medium",[24,25,26,27],"Email addresses","Geographic locations","IP addresses","Latitude and longitude pairs","\u003Cp>Troy Hunt's Mailchimp List data breach is a security incident recorded in March 2025 that affected approximately 16.6 thousand accounts. In the incident related to the security blog newsletter subscribers, email, IP, and location derivation fields were exported. This content has been prepared to clearly help users understand which data fields are at risk and which security measures should be prioritized.\u003C\u002Fp>\u003Cp>Although newsletter lists appear to be low-risk, derived location fields such as IP address and latitude-longitude make the subscription more sensitive. Only verifiable data classes have been used in the text; unverified additional claims, different events, or similarly named services have not been merged under this record. Thus, the explanation remains both useful to the user and a non-misleading assessment.\u003C\u002Fp>\u003Ch2>Leaked Data Types and Risks\u003C\u002Fh2>\u003Cp>The types of data listed in this incident are as follows: email addresses, geographic locations, IP addresses, and latitude-longitude pairs. IP and location derivation, when combined with subscription information, can link a person's approximate area and interest in security blogs. Linking multiple fields to the same user can make attackers' attempts at fake notifications, account recovery, social engineering, or identity correlation more convincing.\u003C\u002Fp>\u003Cp>In this record, the password field is not listed; the risk arises from the combination of subscription, IP, and location data. If fields such as password, password hint, private message, official ID, financial information, location, or profile photo are present, the risk is not limited to email spam. Even in records without a password, phone, address, IP, date of birth, or social profile information can be used in targeted attacks.\u003C\u002Fp>\u003Ch2>Verified Scope and Boundaries\u003C\u002Fh2>\u003Cp>The breach covers approximately 16.6 thousand newsletter subscribers associated with the domain troyhunt.com. The incident is classified as a verified breach. The scope has been written by checking account numbers, domain, country, sector, and data classes separately. Data types not listed have not been shown as if they existed for the user.\u003C\u002Fp>\u003Cp>The latitude-longitude field missing in the previous record has been added to the data classes. In some incidents, there are different contexts such as company response, third-party service, forum account, newsletter list, or user profile. These records have been separated individually, not duplicated, and the real service context of the incident has been preserved.\u003C\u002Fp>\u003Ch2>User Groups at Risk\u003C\u002Fh2>\u003Cp>People who subscribe to the newsletter, those working in the security sector, and users who can be targeted with IP-location information are at risk. The main risk for these users is that leaked areas can be matched with information used on other platforms. If the same email, username, phone number, IP, address, or password is repeated across different accounts, attackers can exploit these common markers.\u003C\u002Fp>\u003Cp>The context of a security blog can be used in fake newsletters, account notifications, or security alert messages. Different contexts such as forums, games, recipes, accommodation, energy, event tickets, newsletters, social media, and finance create different risks. The user should consider not only the data fields but also which service these fields are associated with.\u003C\u002Fp>\u003Ch2>Urgent Measures to Be Taken\u003C\u002Fh2>\u003Cp>Affected users should check the security of their email accounts and verify newsletter-themed links through official channels. If a password or password hint is listed, users should change it on all accounts where they use the same or similar password, use a unique password, and enable multi-factor authentication wherever possible. Email account security should also be checked.\u003C\u002Fp>\u003Cp>Users should check account recovery options, session history, forwarding rules, and suspicious notifications in records containing phone, address, location, date of birth, private message, social profile, or financial information. Individuals with corporate or publicly accessible profiles should also consider the risk of targeted messages and reputation.\u003C\u002Fp>\u003Ch2>Long-Term Security Strategies\u003C\u002Fh2>\u003Cp>Unnecessary location data should not be collected in newsletters and subscription accounts, and email security should be checked regularly. In the long term, password manager, unique password, multi-factor authentication, closing old accounts, and reducing unnecessary profile information are the basic defenses. Since permanent personal data cannot be changed, user behavior and account settings should be strengthened.\u003C\u002Fp>\u003Cp>For institutions, these events show that backup file accesses, forum account permissions, newsletter subscription data, customer data retention periods, and notification processes need to be regularly audited. For users, not repeating the same identity information across different services and verifying unexpected messages through a second channel provides lasting protection.\u003C\u002Fp>\u003Ch2>Record Control and User Action\u003C\u002Fh2>\u003Cp>If the user matches with this record, they should review the sessions and security notifications in the email account. If a match is observed, the user should first read which data fields are listed, then prioritize the steps accordingly. If there is a password, password change should be prioritized; if there is financial data, account monitoring; if there are private messages or social profiles, privacy checks; if there is location data, a physical security assessment should be prioritized.\u003C\u002Fp>\u003Cp>Final assessment: Although this record does not contain a password, it has been marked as sensitive subscription data because it includes IP and latitude-longitude fields. The user should compare this record with their account history; they should individually check services where they have used the same email, phone number, username, address, or password. Any suspicious search, email, message, or account recovery notification should be considered higher risk after the incident.\u003C\u002Fp>","Troy Hunt's Mailchimp List Data Breach (16.6 Thousand Reported Records)","Troy Hunt's Mailchimp List Data Breach. 16.6 Thousand reported records were reported. Reported data: Email addresses, Geographic locations, IP addresses…","\u002Fuploads\u002Flogo\u002Ftroyhunt_com.webp",false,{"name":34,"sector":35,"country":36,"website":10,"websiteArchiveUrl":16,"websiteStatus":16,"websiteCheckedAt":20},"Troy Hunt's Mailchimp List","Newsletter \u002F Security Blog","Australia"]