Detection and removal of predefined sensitive information types from electronic documents

A proxy server comprising:

• at least one memory configured to store computer-readable instructions;
• at least one processor coupled to the at least one memory and configured to execute the computer-readable instructions, the computer-readable instructions configured, upon execution on the at least one processor, to cause the at least one processor to:
• receive, at the proxy server and from a client device, a content request comprising a resource identifier;
• in response to the content request, retrieve web content associated with the resource identifier;
• generating, based on the web content, modified web content comprising proxy client code, wherein the proxy client code is added to the web content to generate the modified web content;
• and
• transmitting the modified web content to the client device, whereby the proxy client code is executed on the client device;
• receive, at the proxy server and from the client device, an upload request comprising a document;
• detect, in the upload request, marker data inserted by the client proxy code executed on the client device;
• responsive to the detecting of the marker data in the upload request, cause redaction from the document, resulting in a redacted document;
• generate a proxied upload request comprising the redacted document;
• and
• transmit the proxied upload request to an upstream server.

A non-transitory computer-readable storage medium configured to store computer-readable instructions, the computer-readable instructions configured, upon execution on at least one processor, to cause the at least one processor to implement operations comprising:

• receiving a message from a client device;
• determining an entity identifier associated with the message;
• obtaining an electronic document associated with the message;
• and
• identifying, in the electronic document, a group of redaction candidates, each redaction candidate of the group of redaction candidates comprising a document portion associated with one of a plurality of sensitive information categories, a first redaction candidate of the group of redaction candidates being associated with a particular sensitive information category of the plurality of sensitive information categories and matches the entity identifier itself and a second redaction candidate of the group of redaction candidates being associated with the particular sensitive information category and does not match the entity identifier itself;
• filtering, from the group of redaction candidates, ones of the redaction candidates that match the entity identifier itself, resulting in a group of filtered redaction candidates that excludes at least the first redaction candidate based on the first redaction candidate matching the entity identifier itself;
• and
• removing only the group of filtered redaction candidates from the electronic document, resulting in a redacted document comprising the first redaction candidate and not the second redaction candidate.