Foxit PDF Reader before 4.2.0.0928 does not properly bound-check the /Title entry in the PDF Info dictionary. A specially crafted PDF with an overlong Title string can overflow a fixed-size stack buffer, corrupt the Structured Exception Handler (SEH) chain, and lead to arbitrary code execution in the context of the user who opens the file.
A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).