Live XSS Flaw Exists in DMCA-dot-com

The user interface of the takedowns website DMCA-dot-com has an active cross-site scripting (XSS) vulnerability. It’s been there for almost a year and has not been addressed. 

After more than a year of attempting and failing to convince DMCA-dot-com to take the XSS seriously, Infosec researcher Joel Ossi, founder of Dutch security firm Websec, disclosed his findings. “I registered at DMCA at first with an intention to protect my own website,” he blogged, explaining that he found unescaped free-text entry boxes in the DMCA user interface that allowed him to create an XSS. 

A copyright takedown service is DMCA-dot-com. Users pay the site to conduct the time-consuming task of obtaining an alleged copyright infringer’s work to be removed from the Internet utilising the infamous US Digital Millennium Copyright Act. The cost of a takedown could be as high as $199. 

On a video conference with The Register, Ossi shared his findings in real-time. The typical XSS tell-tale — a popup with a personalized message – displayed every time he navigated to a new webpage in the DMCA-dot-com user area. The script for doing so was actually fairly straightforward: When he originally discovered the flaw in late 2020, he spent a year attempting and failed to obtain the attention of the operators of DMCA-dot-com.