+--- xpdf/Decrypt.cc.orig 2010-01-28 14:19:51.000000000 -0800
++++ xpdf/Decrypt.cc 2010-02-02 16:04:53.000000000 -0800
+@@ -596,6 +596,7 @@
+ s->bufIdx = 0;
+ if (last) {
+ n = s->buf[15];
++ if(!n || n>16) n=16;
+ for (i = 15; i >= n; --i) {
+ s->buf[i] = s->buf[i-n];
+ }