diff --git a/modules/util/path.go b/modules/util/path.go
index 0883349a88e..5679fa3f595 100644
--- a/modules/util/path.go
+++ b/modules/util/path.go
@@ -360,7 +360,7 @@ func IsReadmeFileExtension(name string, ext ...string) (int, bool) {
 		}
 	}
 
-	if name[6] == '.' {
+	if len(name) > 6 && name[6] == '.' {
 		return len(ext), true
 	}
 
diff --git a/modules/util/path_test.go b/modules/util/path_test.go
index 74adc44a89c..cb38644479d 100644
--- a/modules/util/path_test.go
+++ b/modules/util/path_test.go
@@ -142,6 +142,10 @@ func TestMisc_IsReadmeFileName(t *testing.T) {
 		assert.Equal(t, testCase.expected, ok)
 		assert.Equal(t, testCase.idx, idx)
 	}
+
+	idx, ok := IsReadmeFileExtension("readme", ".md")
+	assert.False(t, ok)
+	assert.Zero(t, idx)
 }
 
 func TestCleanPath(t *testing.T) {