diff --git a/core/fpdfapi/parser/cpdf_parser.cpp b/core/fpdfapi/parser/cpdf_parser.cpp
index e070d2f..9bb9bf2 100644
--- a/core/fpdfapi/parser/cpdf_parser.cpp
+++ b/core/fpdfapi/parser/cpdf_parser.cpp
@@ -757,14 +757,18 @@
       }
 
       const uint32_t objnum = startnum + i;
-      if (GetObjectType(objnum) == ObjectType::kNull) {
+      if (objnum >= CPDF_Parser::kMaxObjectNumber)
+        continue;
+
+      const ObjectType existing_type = GetObjectType(objnum);
+      if (existing_type == ObjectType::kNull) {
         uint32_t offset = GetVarInt(entrystart + WidthArray[0], WidthArray[1]);
         if (pdfium::base::IsValueInRangeForNumericType<FX_FILESIZE>(offset))
           m_CrossRefTable->AddNormal(objnum, 0, offset);
         continue;
       }
 
-      if (GetObjectType(objnum) != ObjectType::kFree)
+      if (existing_type != ObjectType::kFree)
         continue;
 
       if (type == ObjectType::kFree) {