Troj/PDFJs-GE is a variant in the PDFJs family.
PDFJs Trojans exploit JavaScript parsing flaws in Adobe's popular Adobe Reader software. This variant targets computers with unpatched versions of Adobe Reader.
The malicious JavaScript resides within the annotation section of the PDF. A description of this technique can be seen in the SophosLabs blog article
"Yuletide PDF gymnastics".
A temporary mitigation technique that can defend against this and similar attacks is to
disable JavaScript within Adobe Reader.
Troj/PDFJs-GE has been used to distribute Sinowal (detected as
Mal/Sinowa-A) and other malware.