Computer security system with remote browser isolation using forward proxying

A computer system comprising a processor and memory, the computer system configured to:

• transmit, over a computer network, a permission-object that i) specifies that a client-user is an authorized user of a network-provided service;
• and ii) comprises an access-override field that specifies a network address of a remote browser isolation (RBI) host;
• wherein a schema for the permission-object defines:
• the access-override field as being free of user-specific characters;
• and
• other fields as containing user-specific characters including at least one cryptographic signature.

A computer system comprising a processor and memory, the computer system configured to:

• communicate, over a computer network, a permission-object that specifies that a client-user is an authorized user of a network-provided service, wherein the generation of the permission-object comprises creating the permission-object to comprise, at the time of creation, an access-override field that specifies a network address of a remote browser isolation (RBI) host;
• wherein a schema for the permission-object defines:
• the access-override field as being free of user-specific characters;
• and
• other fields as containing user-specific characters including at least one cryptographic signature.