Copy Fail (CVE-2026-31431): a 732-byte Python script gets root on every Linux box since 2017

Server rack with rack-mounted Linux servers — cover for Copy Fail CVE-2026-31431 commentary, photo by Sejio402 on Pexels

CISA added CVE-2026-31431 — nicknamed “Copy Fail” — to its Known Exploited Vulnerabilities catalog on May 1. Eight days later it’s still under-discussed for what it is: a 732-byte Python script that gets you root on every Linux box running …