diff --git a/src/core/standard_fonts.js b/src/core/standard_fonts.js
index 94017aded..88f22a4a6 100644
--- a/src/core/standard_fonts.js
+++ b/src/core/standard_fonts.js
@@ -574,6 +574,39 @@ const getGlyphMapForStandardFonts = getLookupTableFactory(function (t) {
   t[598] = 1068;
   t[599] = 1069;
   t[600] = 1070;
+  t[601] = 1071;
+  t[602] = 1072;
+  t[603] = 1073;
+  t[604] = 1074;
+  t[605] = 1075;
+  t[606] = 1076;
+  t[607] = 1077;
+  t[608] = 1078;
+  t[609] = 1079;
+  t[610] = 1080;
+  t[611] = 1081;
+  t[612] = 1082;
+  t[613] = 1083;
+  t[614] = 1084;
+  t[615] = 1085;
+  t[616] = 1086;
+  t[617] = 1087;
+  t[618] = 1088;
+  t[619] = 1089;
+  t[620] = 1090;
+  t[621] = 1091;
+  t[622] = 1092;
+  t[623] = 1093;
+  t[624] = 1094;
+  t[625] = 1095;
+  t[626] = 1096;
+  t[627] = 1097;
+  t[628] = 1098;
+  t[629] = 1099;
+  t[630] = 1100;
+  t[631] = 1101;
+  t[632] = 1102;
+  t[633] = 1103;
   t[672] = 1488;
   t[673] = 1489;
   t[674] = 1490;
diff --git a/test/pdfs/.gitignore b/test/pdfs/.gitignore
index cb41f1d0a..fec8b0d46 100644
--- a/test/pdfs/.gitignore
+++ b/test/pdfs/.gitignore
@@ -672,6 +672,7 @@
 !issue17730.pdf
 !bug1883609.pdf
 !issue19550.pdf
+!issue20453.pdf
 !issue17808.pdf
 !issue17871_bottom_right.pdf
 !issue17871_top_right.pdf
diff --git a/test/pdfs/issue20453.pdf b/test/pdfs/issue20453.pdf
new file mode 100644
index 000000000..1285d9731
Binary files /dev/null and b/test/pdfs/issue20453.pdf differ
diff --git a/test/test_manifest.json b/test/test_manifest.json
index da5707fd0..f75fcdb18 100644
--- a/test/test_manifest.json
+++ b/test/test_manifest.json
@@ -4549,6 +4549,13 @@
     "rounds": 1,
     "type": "eq"
   },
+  {
+    "id": "issue20453",
+    "file": "pdfs/issue20453.pdf",
+    "md5": "20B5F2A2EA2933328EDF023EF48A0759",
+    "rounds": 1,
+    "type": "eq"
+  },
   {
     "id": "issue19611",
     "file": "pdfs/issue19611.pdf",