Sesame Street fans visiting the program's YouTube channel yesterday found something they weren't expecting - hardcore porn.
The pornographic content was up for about 20 minutes, and the title was changed to 'Sesame Street, it's where porn lives' before the channel was suspended for violation of guidelines.
It's not clear who carried out the hack.
"WHO DOESN'T LOVE PORN KIDS? RIGHT! EVERYONE LOVES IT! I'M MREDXWX AND MY PARTNER MRSUICIDER91 ARE HERE TO BRING YOU MANY NICE CONTENT! PLEASE DON'T LET SESAME STEET TO GET THIS ACCOUNT BACK KIDS," read a statement on the hacked channel profile.
However, Mredxwx took to YouTube himself to deny responsibility, saying: "I did not hack Sesame Street. I am an honest youtuber. I work hard to make quality gameplayer videos AND MOST IMPORTANT I RESPECT THE COMMUNITY GUIDELINES'.
Security expert Graham Cluley of Sophos says it's unclear exactly how the channel got hacked, but that it was probably through sloppiness over passwords.
"What would Bert and Ernie say?" he says.
" The truth of the matter is that the channel is regularly visited by young children, and parents trust that the page will be safe for them to view."