--- /QCodec.java	2023-07-05 02:20:11.490122646 +0200
+++ /Codec-1/src/java/org/apache/commons/codec/net/QCodec.java	2023-07-05 02:20:11.490122646 +0200
@@ -159,7 +159,7 @@
         if (hasUnderscores) {
             byte[] tmp = new byte[bytes.length];
             for (int i = 0; i < bytes.length; i++) {
-                byte b = bytes[i];
+byte b = tmp[i];
                 if (b != UNDERSCORE) {
                     tmp[i] = b;
                 } else {
