--- poppler/Hints.cc.orig	2016-08-02 11:25:28.485597235 -0700
+++ poppler/Hints.cc	2016-08-02 12:41:00.545596695 -0700
@@ -292,6 +292,11 @@
      nSharedGroups = 0;
      return;
   }
+  if (nBitsNumObjects > 32 || nBitsDiffGroupLength > 32) {
+     error(errSyntaxWarning, -1, "Invalid shared object groups bit length");
+     nSharedGroups = 0;
+     return;
+  }
 
   groupLength = (Guint *) gmallocn_checkoverflow(nSharedGroups, sizeof(Guint));
   groupOffset = (Guint *) gmallocn_checkoverflow(nSharedGroups, sizeof(Guint));
@@ -421,23 +426,18 @@
 
 Guint Hints::readBits(int n, Stream *str)
 {
-  Guint bit, bits;
+  Guint bits = 0;
 
   if (n < 0) return -1;
-  if (n == 0) return 0;
 
-  if (n == 1)
-    return readBit(str);
-
-  bit = (readBit(str) << (n-1));
-  if (bit == (Guint) -1)
-    return -1;
-
-  bits = readBits(n-1, str);
-  if (bits == (Guint) -1)
-    return -1;
+  while (--n >= 0) {
+    Guint bit = readBit(str);
+    if (bit == (Guint) -1)
+      return -1;
+    bits |= bit << n;
+  }
 
-  return bit | bits;
+  return bits;
 }
 
 int Hints::getPageObjectNum(int page) {