Threat Research Blog

In Turn, It's PDF Time

[Update: February 13, 2013] We have found IE, Java, and Flash zero-days in a row in the past several months, and now it's PDF’s turn. Today, we identified that a PDF zero-day is being exploited in the wild, and we observed successful exploitation on the latest Adobe PDF Reader 9.5.3, 10.1.5, and 11.0.1.

Upon successful exploitation, it will drop two DLLs. The first DLL shows a fake error message and opens a decoy PDF document, which is usually common in targeted attacks. The second DLL in turn drops the callback component, which talks to a remote domain.


We have already submitted the sample to the Adobe security team. Before we get confirmation from Adobe and a mitigation plan is available, we suggest that you not open any unknown PDF files. We will continue our research and continue to share more information.

[Update: February 13, 2013]

In response to the many requests we’ve received for more detailed information, we would like to let our readers know that we have been working with Adobe and have jointly agreed to refrain from posting the technical details of the zero-day at this time. This post was intended to serve as a warning to the general public. We will update this post with more information at a later time.

This blog is written by FireEye researchers Yichong Lin, Thoufique Haq, and James Bennett.