Eliminating abuse caused by password reuse in different systems

A non-transitory machine-readable medium having stored thereon machine-readable instructions executable to cause a machine to perform operations comprising:

• receiving, from a first server machine associated with a first organization, a first security request comprising first authentication data usable to authenticate a user with the first organization, wherein the first security request is addressed to the machine for detecting reuse of the first authentication data by the user with another organization;
• identifying a plurality of organizations to detect reuse of the first authentication data based at least in part on analyzing the first security request;
• generating a second security request comprising at least a portion of the first authentication data;
• sending the second security request to each one of a plurality of server machines associated with the plurality of organizations;
• receiving a plurality of responses from the plurality of server machines;
• analyzing the plurality of responses to determine whether the first authentication data is reused by the user with at least one of the plurality of organizations;
• and
• in response to determining that the first authentication data is reused by the user with at least one of the plurality of organizations, providing an alert indicating that the first authentication data was reused by the user with a different organization.

A computer-implemented method for detecting reuse of authentication data in different organizations, comprising:

• receiving, by one or more hardware processors of a computer system from a first server machine associated with a first organization, a first security request comprising a first anonymized version of first authentication data usable for authenticating a user with the first organization, wherein the first security request is addressed to the computer system for detecting reuse of the first authentication data by the user with at least one other organization;
• identifying, by the one or more hardware processors among a plurality of organizations, a second organization to detect reuse of the first authentication data based on one or more criteria associated with the first security request;
• generating, by the one or more hardware processors, a second security request comprising a second anonymized version of the first authentication data;
• sending, by the one or more hardware processors, the second security request to a second server machine associated with the identified second organization;
• receiving, by the one or more hardware processors, a response comprising second authentication data usable to authenticate the user with the second organization;
• analyzing, by the one or more hardware processors, the response to determine whether the first authentication data matches the second authentication data;
• and
• in response to determining that the first authentication data matches the second authentication data, providing, by the one or more hardware processors to the first server machine, an alert indicating that the first authentication data was reused by the user with a different organization.