Exploits to Adobe Reader in the form of malicious PDF files continue to pose an in-the-wild threat for unpatched users.
The issue: A trojan can be installed on unpatched users' machines if they unknowingly access a malicious website or are redirected there from malicious banners and ads, according to Trend Micro's research labs. Adobe issued a new version of Adobe Reader on Nov. 4 to address the latest flaws.
Whomever was responsible for the initial attacks, which struck soon after the new version was released, appear to have created a slightly different variant that is evading detection by most anti-virus solutions, wrote Swa Frantzen, handler at the SANS Internet Storm Center.
The new PDF has similar content and was discovered on the same website the initial file was hosted, he wrote.
The attack works when a PDF with embedded exploit code is hosted on a website. When a user visits the website, the hostile code is loaded by the vulnerable package -- in this case Adobe Reader -- onto the user's computer, Ken Dunham, director of global response for iSight Partners, told SCMagazineUS.com WednesdayDunham said it is normal for anti-virus solutions to miss emerging threats. On average, AV companies are slow to respond, taking about one to six months to process the average threat.
“Bad actors normally test their code to make sure it's not detected before launching it,” Dunham said. “So you can be sure your anti-virus isn't going to detect it.”
“If you thought your AV was going to protect you, you're wrong,” Dunham said. “AV isn't going to protect you from the latest and greatest threats.”