Xpdf, GPdf: Stack overflow in Decrypt::makeFileKey2

Background Xpdf is an open source viewer for Portable Document Format PDF files. GPdf is a Gnome-based PDF viewer that includes some Xpdf code. Description iDEFENSE reports that the Decrypt::makeFileKey2 function in Xpdf's Decrypt.cc insufficiently checks boundaries when processing /Encrypt /Leng...