diff --git a/libwvdrmengine/cdm/metrics/include/value_metric.h b/libwvdrmengine/cdm/metrics/include/value_metric.h
index 19bf6924..6fb4a3ff 100644
--- a/libwvdrmengine/cdm/metrics/include/value_metric.h
+++ b/libwvdrmengine/cdm/metrics/include/value_metric.h
@@ -100,7 +100,7 @@ class ValueMetric {
       return value_proto;
     }
 
-    return NULL;
+    return nullptr;
   }
 
  private:
diff --git a/libwvdrmengine/cdm/util/src/string_conversions.cpp b/libwvdrmengine/cdm/util/src/string_conversions.cpp
index e309f7dd..b2566e65 100644
--- a/libwvdrmengine/cdm/util/src/string_conversions.cpp
+++ b/libwvdrmengine/cdm/util/src/string_conversions.cpp
@@ -29,7 +29,7 @@ static const char kBase64Codes[] =
 
 int DecodeBase64Char(char c) {
   const char* it = strchr(kBase64Codes, c);
-  if (it == NULL) return -1;
+  if (it == nullptr) return -1;
   return it - kBase64Codes;
 }