The official Barclays Premier League Fantasy Football website has been targeted by criminals hoping to trick its users into downloading the Nuclear exploit kit.
The flash-based advert for a British yacht company, calling itself OKzilla, was being displayed to the website's 16 million users, automatically redirecting them to the malware download page.
The server IP was hidden behind CloudFlare making it difficult to find out the true owner of the website, although Who Is revealed it was registered using GoDaddy. A script then forwarded the user to Kanenia.info, another address hiding behind CloudFlare, which hosted a Google shortened URL where the Nuclear exploit kit was hidden.
The Nuclear exploit kit actually takes advantage of the Flash player installed on a user's machine, compromising the information stored on it. This particular type of malware is commonly responsible for launching zero-day attacks, which can in turn be used to infiltrate data from a user's machine.
MalwareBytes, which discovered the flaw, said it would have been difficult for unsuspecting users to realise they were being taken to a malicious site because it used the secure https protocol, encrypting the content of the page. Additionally, it used a shortened Google url, making it appear more trustworthy than it was.
"The malvertising chain is familiar as it makes use of goo.gl URLs (Google URL shortener) which are injected dynamically within compromised or blackhat sites," Jerome Segura said on the company's blog. "Those shortened URLs are used and discarded frequently and yet, because they belong to Google, a trusted company, cannot be blacklisted entirely at the root domain level."
MalwareBytes said it alerted the Premier League fantasy website to the malvertising and told Google that its shortened URLs were being used for malicious activities.
