diff --git a/infoschema/tables.go b/infoschema/tables.go
index 656a99f52d838..8df6cab9cb84c 100644
--- a/infoschema/tables.go
+++ b/infoschema/tables.go
@@ -1729,8 +1729,8 @@ func FormatTiDBVersion(TiDBVersion string, isDefaultVersion bool) string {
 
 	// The user hasn't set the config 'ServerVersion'.
 	if isDefaultVersion {
-		nodeVersion = TiDBVersion[strings.LastIndex(TiDBVersion, "TiDB-")+len("TiDB-"):]
-		if nodeVersion[0] == 'v' {
+		nodeVersion = TiDBVersion[strings.Index(TiDBVersion, "TiDB-")+len("TiDB-"):]
+		if len(nodeVersion) > 0 && nodeVersion[0] == 'v' {
 			nodeVersion = nodeVersion[1:]
 		}
 		nodeVersions := strings.Split(nodeVersion, "-")
diff --git a/infoschema/tables_test.go b/infoschema/tables_test.go
index 3650f2833a1a6..aee92b0afed70 100644
--- a/infoschema/tables_test.go
+++ b/infoschema/tables_test.go
@@ -676,8 +676,14 @@ func TestSelectHiddenColumn(t *testing.T) {
 
 func TestFormatVersion(t *testing.T) {
 	// Test for defaultVersions.
-	defaultVersions := []string{"5.7.25-TiDB-None", "5.7.25-TiDB-8.0.18", "5.7.25-TiDB-8.0.18-beta.1", "5.7.25-TiDB-v4.0.0-beta-446-g5268094af"}
-	defaultRes := []string{"None", "8.0.18", "8.0.18-beta.1", "4.0.0-beta"}
+	defaultVersions := []string{
+		"5.7.25-TiDB-None",
+		"5.7.25-TiDB-8.0.18",
+		"5.7.25-TiDB-8.0.18-beta.1",
+		"5.7.25-TiDB-v4.0.0-beta-446-g5268094af",
+		"5.7.25-TiDB-",
+		"5.7.25-TiDB-v4.0.0-TiDB-446"}
+	defaultRes := []string{"None", "8.0.18", "8.0.18-beta.1", "4.0.0-beta", "", "4.0.0-TiDB"}
 	for i, v := range defaultVersions {
 		version := infoschema.FormatTiDBVersion(v, true)
 		require.Equal(t, defaultRes[i], version)