Rapid7 conducted a zero-day research project into multifunction printers (MFP) from Brother Industries, Ltd. — discovering 8 new vulnerabilities. Learn more!
Brother has indicated that this vulnerability cannot be fully remediated in firmware, and has required a change to the manufacturing process of all affected models.
The toner thing was based entirely in a single 3 year old unverified Reddit post. There is zero evidence that Brother has ever blocked 3rd party toner, and plenty of evidence that 3rd party toner works just fine, even with the most recent firmware. These rumors need to stop.