diff --git a/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java b/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
index 136c0c4..14fc366 100644
--- a/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
+++ b/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
@@ -1297,7 +1297,8 @@
         ArrayList<PendingAttribute> bigrams = null;
         if (0 != (flags & FormatSpec.FLAG_HAS_BIGRAMS)) {
             bigrams = new ArrayList<PendingAttribute>();
-            while (true) {
+            int bigramCount = 0;
+            while (bigramCount++ < FormatSpec.MAX_BIGRAMS_IN_A_GROUP) {
                 final int bigramFlags = buffer.readUnsignedByte();
                 ++addressPointer;
                 final int sign = 0 == (bigramFlags & FormatSpec.FLAG_ATTRIBUTE_OFFSET_NEGATIVE)
@@ -1325,6 +1326,9 @@
                         bigramAddress));
                 if (0 == (bigramFlags & FormatSpec.FLAG_ATTRIBUTE_HAS_NEXT)) break;
             }
+            if (bigramCount >= FormatSpec.MAX_BIGRAMS_IN_A_GROUP) {
+                MakedictLog.d("too many bigrams in a group.");
+            }
         }
         return new CharGroupInfo(originalGroupAddress, addressPointer, flags, characters, frequency,
                 parentAddress, childrenAddress, shortcutTargets, bigrams);
diff --git a/java/src/com/android/inputmethod/latin/makedict/FormatSpec.java b/java/src/com/android/inputmethod/latin/makedict/FormatSpec.java
index 5ef35a1..3fd9e40 100644
--- a/java/src/com/android/inputmethod/latin/makedict/FormatSpec.java
+++ b/java/src/com/android/inputmethod/latin/makedict/FormatSpec.java
@@ -216,6 +216,7 @@
 
     static final int MAX_CHARGROUPS_FOR_ONE_BYTE_CHARGROUP_COUNT = 0x7F; // 127
     static final int MAX_CHARGROUPS_IN_A_NODE = 0x7FFF; // 32767
+    static final int MAX_BIGRAMS_IN_A_GROUP = 10000;
 
     static final int MAX_TERMINAL_FREQUENCY = 255;
     static final int MAX_BIGRAM_FREQUENCY = 15;