diff --git a/src/core/fonts.js b/src/core/fonts.js
index 5dfbab374..d9bf1d6f0 100644
--- a/src/core/fonts.js
+++ b/src/core/fonts.js
@@ -4236,9 +4236,10 @@ var Font = (function FontClosure() {
             if (!glyphName) {
               continue;
             }
-            var unicodeOrCharCode;
+            var unicodeOrCharCode, isUnicode = false;
             if (cmapPlatformId === 3 && cmapEncodingId === 1) {
               unicodeOrCharCode = GlyphsUnicode[glyphName];
+              isUnicode = true;
             } else if (cmapPlatformId === 1 && cmapEncodingId === 0) {
               // TODO: the encoding needs to be updated with mac os table.
               unicodeOrCharCode = Encodings.MacRomanEncoding.indexOf(glyphName);
@@ -4246,8 +4247,11 @@ var Font = (function FontClosure() {
 
             var found = false;
             for (i = 0; i < cmapMappingsLength; ++i) {
-              if (cmapMappings[i].charCode === unicodeOrCharCode &&
-                  hasGlyph(cmapMappings[i].glyphId, unicodeOrCharCode, -1)) {
+              if (cmapMappings[i].charCode !== unicodeOrCharCode) {
+                continue;
+              }
+              var code = isUnicode ? charCode : unicodeOrCharCode;
+              if (hasGlyph(cmapMappings[i].glyphId, code, -1)) {
                 charCodeToGlyphId[charCode] = cmapMappings[i].glyphId;
                 found = true;
                 break;
diff --git a/test/pdfs/.gitignore b/test/pdfs/.gitignore
index 0445acb12..9a9a81ab8 100644
--- a/test/pdfs/.gitignore
+++ b/test/pdfs/.gitignore
@@ -95,6 +95,7 @@
 !issue5599.pdf
 !issue5747.pdf
 !issue6099.pdf
+!issue6336.pdf
 !gradientfill.pdf
 !bug903856.pdf
 !bug850854.pdf
diff --git a/test/pdfs/issue6336.pdf b/test/pdfs/issue6336.pdf
new file mode 100644
index 000000000..5bfa8d168
Binary files /dev/null and b/test/pdfs/issue6336.pdf differ
diff --git a/test/test_manifest.json b/test/test_manifest.json
index 06554677d..4fcb797dd 100644
--- a/test/test_manifest.json
+++ b/test/test_manifest.json
@@ -1182,6 +1182,13 @@
        "link": false,
        "type": "eq"
     },
+    {  "id": "issue6336",
+       "file": "pdfs/issue6336.pdf",
+       "md5": "1c457c12b3606e1de610235d6768bd78",
+       "rounds": 1,
+       "link": false,
+       "type": "eq"
+    },
     {  "id": "issue5801",
        "file": "pdfs/issue5801.pdf",
        "md5": "e9548650ad40e13e00d2a486bbc2bb1b",