Researcher shows Microsoft-signed shim can be borrowed to bypass Secure Boot on corporate PCs

A blog post by security researcher Leo Smith describes a technique for abusing a Microsoft-signed boot shim to undermine Secure Boot on corporate hardware. Secure Boot is designed to ensure only trusted, cryptographically signed software loads during startup, which makes a signed component being repurposed a notable concern. The write-up was shared on Hacker News, where it gathered modest early attention with 12 points and one comment. The details suggest the issue relies on trust placed in legitimately signed boot code rather than on a flaw in the signature itself. The post is available on the author's blog for readers who want the full technical account.