KnownCircle Data Breach (2016): What Was Exposed & What To Do
SourceBreach data provided in part by Have I Been Pwned, used under CC BY 4.0.
The KnownCircle Data Breach (2016) (reported April 12, 2016) exposed Email addresses, Email messages, Genders and Names belonging to roughly 2.0M people. If you have an account with them, your information may now be circulating on the open web and with data brokers. Here’s exactly what happened, how to check if you were affected, and what to do next.
What happened
In April 2016 an external party obtained a substantial collection of data from KnownCircle. The material was stored in JSON format and amounted to gigabytes of records connected to real-estate and insurance marketing activities. A small number of staff passwords were present and stored as bcrypt hashes. No further technical details about the method of access or the precise date of the intrusion have been disclosed.
How a breach like this happens
Incidents involving the extraction of customer or operational databases often begin with the compromise of an internet-facing server, an application vulnerability, or the use of stolen credentials. Once access is gained, an actor can copy files or database contents without triggering immediate detection. Data of this kind is sometimes later posted or shared in public or semi-public locations, after which researchers or security teams identify and report its presence.
About KnownCircle
KnownCircle operated a marketing-automation platform aimed at agents and professional service providers. Its services supported outreach in the real-estate and insurance industries, where contact information and campaign logs are routinely collected. Because the company is now defunct, the records represent a static snapshot of data that was once actively used for business communications.
What data was at risk
The exposed records included email addresses, email messages, genders, names, passwords, phone numbers, and physical addresses. The material also contained logs of emails sent and records related to gift-card tracking. The exact scope of every field present in the dataset remains unconfirmed beyond these categories.
Why it matters
Exposure of names, addresses, phone numbers, and email content can enable unsolicited contact or more targeted social-engineering attempts. Passwords, even when hashed, may be tested against other accounts if users reused credentials. For the organisation, the incident illustrates the long-term retention of marketing data whose value persists after the service itself has ceased operation.
If your data was in this breach
Review any accounts that still use the exposed email address or phone number and change passwords where reuse is suspected. Enable multi-factor authentication on important services. Individuals can run a free exposure scan of their email address against known breach data to determine whether their information appears in public records of this or other incidents.
AICompiled with AI assistance from public sources and published under our editorial standards.
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Read GalaxyWarden’s full analysis of the KnownCircle Data Breach (2016) →
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