SuSE reported a buffer overflow in FoFiType1::parse affecting older xpdf versions.  Code snippets from fofi/FoFiType1.cc:

 133 void FoFiType1::parse() {
 ...
 163       line = getNextLine(line);
 164       for (j = 0; j < 300 && line; ++j) {
 165         line1 = getNextLine(line);
 166         if ((n = line1 - line) > 255) {
 167           n = 255;
 168         }
 169         strncpy(buf, line, n);

getNextLine can, however, return NULL:

 117 char *FoFiType1::getNextLine(char *line) {
 118   while (line < (char *)file + len && *line != '\x0a' && *line != '\x0d') {
 119     ++line;
 120   }
 121   if (line < (char *)file + len && *line == '\x0d') {
 122     ++line;
 123   }
 124   if (line < (char *)file + len && *line == '\x0a') {
 125     ++line;
 126   }
 127   if (line >= (char *)file + len) {
 128     return NULL;
 129   }

Therefore, (line1 - line) is not defined / results in negative value n.  That value is later passed to strncpy, causing overflow of buf buffer.