LOW-LATENCY, OUTBOUND MESSAGE MONITORING, CONTROL, AND AUTHENTICATION

A platform may receive configuration information of individual user authorizations for outbound messaging through specification of one or more authorized vendors. The platform maintains a list of the vendors and, for each vendor, a DKIM public key associated with the vendor, without publishing the public keys to a DNS, and publishes a customized SPF policy comprising a macro mechanism for identifying a particular user that transmitted a message to the DNS. The platform logs received SPF customized queries, extracts data populated by the macro mechanism from the logged queries, and analyzes the extracted data to determine a particular user associated with the query, to determine whether the user is authorized to utilize a vendor associated with the domain based on the configuration information. Responsive to the determination that the individual is authorized to utilize the vendor, the platform publishes the DKIM public key associated with the vendor to the DNS.