In Xpdf 4.01.01, a buffer over-read could be triggered in FoFiType1C::convertToType1 in fofi/FoFiType1C.cc when the index number is larger than the charset array bounds. It can, for example, be triggered by sending a crafted PDF document to the pdftops tool. It allows an attacker to use a crafted pdf file to cause Denial of Service or an information leak, or possibly have unspecified other impact.