There&apos;s a line of Casio calculators which has a dot-matrix LCD display and a 8-bit CPU of an obscure architecture called nX-U8/100.<br><br>Eventually, a way to make the Harvard-architecture CPU jump to arbitrary locations was discovered, and this combined with a manually dumped ROM image allows to execute arbitrary code using ROP.<br><br>The method of achieving a buffer overflow was originally discovered by a small group of calculator hackers on Baidu and that discovery makes the above possible.<br><br>Our research on <a target="_blank" rel="noopener noreferrer" href="http://casiocalc.org">casiocalc.org</a> has yielded the necessary documentation on the rare CPU and its architecture, and we plan on writing a custom loader to make this exploit more convenient to use. We have also developed an open-source emulator for the calculator to aid research.