CVE-2026-31431 Copy Fail: A Nine-Year-Old Kernel Bug, a 732-Byte Script, and a Root Shell
On April 29, 2026, CVE-2026-31431 was publicly disclosed. Nicknamed “Copy Fail”, it is a local privilege escalation in the Linux kernel with a CVSS score of 7.8, present in every major distribution running kernel 4.13 or later: Ubuntu, RHEL, Amazon Linux, SUSE, Rocky Linux. What makes it stand out from most CVEs in this class is how little an attacker needs: a 732-byte Python script, standard library only, no compilation, no race conditions, no kernel offsets. First try, every time. ...