Close this port!

A grey-hat hacker going by the name of Stackoverflowin has pwned over 150,000 printers that have been left accessible online. For the past 24 hours, Stackoverflowin has been running an automated script that searches for open printer ports and sends a rogue print job to the target’s device. The script targets IPP (Internet Printing Protocol) ports, LPD (Line Printer Daemon) ports, and port 9100 left open to external connections. From high-end multi-functional printers at corporate headquarters to lowly receipt printers in small town restaurants, all have been affected. The list includes brands such as Afico, Brother, Canon, Epson, HP, Lexmark, Konica Minolta, Oki, and Samsung. The printed out message included recommendations for printer owners to secure their device. The hacker said that people who reached out were very nice and thanked him. The printers apparently spew out an ASCII drawing of a robot, along with the words “stackoverflowin the hacker god has returned. your printer is part of a flaming botnet… For the love of God, please close this port.” The messages sometimes also include a link to a Twitter feed named LMAOstack.