COPY FAIL: 732 BYTES TO ROOT ON EVERY MAJOR LINUX DISTRIBUTION

Summary from the TLDR newsletter

Copy Fail is a logic bug in the Linux kernel's authencesn cryptographic template that lets unprivileged users trigger a deterministic, controlled 4-byte write into the page cache of any readable file on the system. It can be exploited using a single 732-byte Python script to obtain root on essentially all Linux distributions shipped since 2017. Its discovery was AI-assisted. A patch for the bug is available.