Hackers on Thursday exploited a vulnerability on Ain't It Cool News that redirected anyone visiting the movie review site to a server containing a malicious Adobe Reader file.
The attack targeted a vulnerable PHP script on one of AICN's servers that automatically appended the malicious link to banner ads served on the site, its publisher, Roland De Noie, said. As a result, anyone visiting the site over a 90-minute period on Thursday morning was silently redirected to speedconnection .cn which served a malicious file named annonce.pdf.
The booby-trapped PDF, according an analysis by researchers at Praetorian Prefect, exploited two vulnerabilities in Adobe Reader that the company has already fixed. When the file is opened by unpatched versions of Reader, it launches malicious shell code that hijacks the machine. Only 12 of the 41 major anti-virus programs currently detect the trojan, according to this VirusTotal analysis.
In September, Mozilla found that more than half of Firefox users used insecure versions of Adobe Flash. It wouldn't be surprising to find a similarly large proportion of the population using out-of-date versions of Reader, too.
"The point of weakness was actually our own ad server," De Noie told The Register. The unknown attackers "had cracked through a PHP server flaw and appended this link to all the ads."
AICN has yet to warn its users that they may have been attacked. De Noie said his staff was still collecting information.
The attack came as a shock to some AICN readers, many who consider themselves enthusiasts of science-fiction, fantasy and horror films.
"This didn't just happen once, randomly," one reader complained after encountering the poisoned PDF. "It's happened 9-10 times in a row as I accessed the AICN website. Specifically targeting my IP number." ®