A Twitter user using the pseudonym of @TheHackerGiraffe has hacked over 50,000 printers to print out flyers telling people to subscribe to PewDiePie's YouTube channel.

The messages have been sent out yesterday, November 29, and have caused quite the stirr among the users who received them, as they ended up on a bunch of places, from high-end multi-functional printers at large companies to small handheld receipt printers at gas stations and restaurants.

The only condition was that the printer was connected to the Internet, used old firmware, and had "printing" ports left exposed online.

The message the printers received was a simple one. It urged people to subscribe to PewDiePie's YouTube channel in order for PewDiePie --a famous YouTuber from Sweden, real name Felix Kjellberg-- to keep the crown of most subscribed to YouTube channel.

If this sounds ...odd... it's because over the past month, an Indian record label called T-Series has caught up and surpassed PewDiePie, once considered untouchable in terms of YouTube followers.

The Swedish Youtube star made a comeback after his fans banded together in various social media campaigns, but T-Series is catching up with PewDiePie again.

The printer hack is just the latest effort from PewDiePie and his fans to get new followers, efforts which also include the YouTuber putting out a NSFW rap video.

Right now, subscriber counts stand at 72.6 million for PewDiePie and 72.5 for T-Series.

As for the technical side of the hack, this wasn't complicated at all, and neither was it original. The hack is one of the most basic tricks one can pull off, and has been done before numerous times, first by a famous hacker named Weev, who made thousands of Internet-connected printers spew out anti-Semitic messages in March 2016, and then again in February 2017 by another hacker who printed silly drawings on over 150,000 printers.

The hack relies on using automated scripts to send print messages to printers that have IPP (Internet Printing Protocol) ports, LPD (Line Printer Daemon) ports, and port 9100 left open over the Internet.

In a Reddit AMA after The Verge first covered his "hacks," @TheHackerGiraffe said he hacked only 50,000 printers, but he could have easily pushed his message to over 800,000 that are currently exposed online.

The pull it off, the hacker said he used a tool called the Printer Exploitation Toolkit (or PRET), which was released in January 2017, when its authors puublished it together with a research paper detailing six vulnerabilities in over 20 network printers, the tool being meant to be used as an utility for testing for vulnerable printers.

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