@Theory
  public void testTagModificationAfterCreateVerification(
      @FromDataPoints("implementationTestVectors") AesCmacTestVector t)
      throws Exception {
    assumeFalse(TinkFips.useOnlyFips());

    ChunkedMac mac = new ChunkedAesCmacImpl(t.key);

    byte[] mutableTag = Arrays.copyOf(t.tag, t.tag.length);
    ChunkedMacVerification macVerification = mac.createVerification(mutableTag);
    mutableTag[0] ^= (byte) 0x01;
    macVerification.update(ByteBuffer.wrap(t.message));
    macVerification.verifyMac();
  }
Finally, here comes a randomized test. In case, for some reason, the above tests do not catch
some bug, we'll have a chance to catch it here.
java_src/src/test/java/com/google/crypto/tink/mac/internal/ChunkedAesCmacTest.java