Ask HN: I found a vulnerability in Dell XPS BIOS, what should I do?

I found a way to "brick" any XPS laptop BIOS with zero data loss or corruption. It will be unable to boot, access BIOS or boot menu. You can repair it without hardware replacement as long as you know where the problem comes from.

Should I build a minimalist PoC before reporting it? Who do I contact to report it?