Security researchers in Japan have discovered a way to abuse a popular blocking feature on social media sites. The side-channel attack exploits the user-blocking function of a social media platform by taking advantage of its feature that requires certain Web pages to return specific Web content. Twitter and eBay have updated their platforms to prevent the attack, and some browsers have added a feature to thwart the attack. The attack, which targets Windows users, employs a combination of cross-site request forgery (CSRF) and timing attacks.”]