Exploit:Win32/Pidief.B is a detection for an exploit that targets a Portable Document Format (PDF) vulnerability. The critical vulnerability could result in the installation of additional malware when a malicious PDF document is opened using Adobe Reader version 9, or earlier.
This exploit may be introduced into the system by viewing or opening a malicious PDF document hosted on a Web site or attached to an e-mail message. Opening the malicious PDF document in an unprotected environment could activate the exploit code on vulnerable systems.
In the wild, exploits have been observed to download malware from the following Web sites using HTTP:
Malicious programs downloaded from the site could be stored into the Windows system folder using filenames such as '~.exe'. At the time of this writing, the HTTP request generates a 404 error (destination requested not found).
Analysis by Wei Li
There are no common symptoms associated with this threat. This exploit is activated when opening malicious PDF documents on vulnerable computers. Alert notifications from installed antivirus software may be the only symptom(s).