diff --git a/src/core/fonts.js b/src/core/fonts.js
index fef393d33..a13a7ea4e 100644
--- a/src/core/fonts.js
+++ b/src/core/fonts.js
@@ -2798,11 +2798,15 @@ var Font = (function FontClosure() {
     };
   }
 
-  function getRanges(glyphs) {
+  function getRanges(glyphs, numGlyphs) {
     // Array.sort() sorts by characters, not numerically, so convert to an
     // array of characters.
     var codes = [];
     for (var charCode in glyphs) {
+      // Remove an invalid glyph ID mappings to make OTS happy.
+      if (glyphs[charCode] >= numGlyphs) {
+        continue;
+      }
       codes.push({ fontCharCode: charCode | 0, glyphId: glyphs[charCode] });
     }
     codes.sort(function fontGetRangesSort(a, b) {
@@ -2831,8 +2835,8 @@ var Font = (function FontClosure() {
     return ranges;
   }
 
-  function createCmapTable(glyphs) {
-    var ranges = getRanges(glyphs);
+  function createCmapTable(glyphs, numGlyphs) {
+    var ranges = getRanges(glyphs, numGlyphs);
     var numTables = ranges[ranges.length - 1][1] > 0xFFFF ? 2 : 1;
     var cmap = '\x00\x00' + // version
                string16(numTables) +  // numTables
@@ -4335,7 +4339,7 @@ var Font = (function FontClosure() {
       this.toFontChar = newMapping.toFontChar;
       tables.cmap = {
         tag: 'cmap',
-        data: createCmapTable(newMapping.charCodeToGlyphId)
+        data: createCmapTable(newMapping.charCodeToGlyphId, numGlyphs)
       };
 
       if (!tables['OS/2'] || !validateOS2Table(tables['OS/2'])) {
@@ -4473,7 +4477,8 @@ var Font = (function FontClosure() {
       builder.addTable('OS/2', createOS2Table(properties,
                                               newMapping.charCodeToGlyphId));
       // Character to glyphs mapping
-      builder.addTable('cmap', createCmapTable(newMapping.charCodeToGlyphId));
+      builder.addTable('cmap', createCmapTable(newMapping.charCodeToGlyphId,
+                       numGlyphs));
       // Font header
       builder.addTable('head',
             '\x00\x01\x00\x00' + // Version number
diff --git a/test/pdfs/.gitignore b/test/pdfs/.gitignore
index 38a33eb86..49ec4bef9 100644
--- a/test/pdfs/.gitignore
+++ b/test/pdfs/.gitignore
@@ -22,6 +22,7 @@
 !bug1020858.pdf
 !bug1050040.pdf
 !bug1200096.pdf
+!issue5564_reduced.pdf
 !canvas.pdf
 !complex_ttf_font.pdf
 !extgstate.pdf
diff --git a/test/pdfs/issue5564_reduced.pdf b/test/pdfs/issue5564_reduced.pdf
new file mode 100644
index 000000000..0eddb63e5
Binary files /dev/null and b/test/pdfs/issue5564_reduced.pdf differ
diff --git a/test/test_manifest.json b/test/test_manifest.json
index 054faf0c4..3452275db 100644
--- a/test/test_manifest.json
+++ b/test/test_manifest.json
@@ -40,6 +40,16 @@
        "type": "load",
        "about": "PDF with undefined stream length."
     },
+    {  "id": "issue5564_reduced",
+       "file": "pdfs/issue5564_reduced.pdf",
+       "md5": "097853614b56fc10bfbf7e56daa0c66b",
+       "rounds": 1,
+       "link": false,
+       "firstPage": 1,
+       "lastPage": 1,
+       "type": "eq",
+       "about": "Causes cmap to be created with invalid glyph ids."
+    },
     {  "id": "bug946506",
        "file": "pdfs/bug946506.pdf",
        "md5": "c28911b5c31bdc337c2ce404c5971cfc",