A part of Donald Trump's campaign website looked different than usual until Monday morning. Its "action" subdomain, which usually houses his calls to action, contained a Turkish message instead. "Do not be like those who forgot Allah, so Ally made them forget themselves. Here they really went astray," the message in Turkish said, according to Newsweek. The page also contained a video embed of Turkish President Recep Tayyip Erdoğan, as well as a link to the hacker's Instagram and Facebook pages.
A hacker calling themselves RootAyyildiz has claimed responsibility for the defacement — and for many others in the past. The National Intelligence Council released a report earlier this year linking them to the defacement of Biden-Harris' presidential campaign website, as well. Back then, Biden's website showed a message in Turkish, the country's flag and a photo of the 34th Sultan of the Ottoman Empire, Abdul Hamid II.
RootAyyildiz told Motherboard that they used a technique called Server Side Template Injection (SSTI) to inject their own code into the site's template and that they had control of the site for three months. According to Forbes, references to RootAyyildiz first appeared on the website on October 9th, at the latest. The hacker added in a statement to Motherboard: "There are many areas of hacking attacks, for example, hacking social media accounts or websites, I am a hacktivist and I have been working on websites for a long time and I choose this management to have my voice heard."
Before the US Presidential Elections last year, hackers were also able to gain control of Trump's website. They replaced its About page with a message threatening to discredit the then-POTUS by sharing incriminating data.