diff --git a/tests/ConstStringTests.cpp b/tests/ConstStringTests.cpp
index 7596c46..62257a9 100644
--- a/tests/ConstStringTests.cpp
+++ b/tests/ConstStringTests.cpp
@@ -44,13 +44,14 @@ TEST_CASE("Use case insensitive const string in switch case", "[Utilities]") {
 
 __attribute__((optnone))
 static Arbutils::CaseInsensitiveConstString TestCreateConstString(){
-    char originalVal [6];
+    char originalVal [7];
     originalVal[0] = 'f';
     originalVal[1] = 'o';
     originalVal[2] = 'o';
     originalVal[3] = 'b';
     originalVal[4] = 'a';
     originalVal[5] = 'r';
+    originalVal[6] = '\0';
     return Arbutils::CaseInsensitiveConstString(originalVal);
 }