Joel B.D.

‼️Copy Fail (CVE-2026-31431) is a Linux privilege escalation bug that lets any local user get root using a 732-byte Python script, and itworks on basically every major Linux distro shipped since 2017. Website: copy.fail Write-up: xint.io/blog/copy-fail… GitHub: github.com/theori-io/copy… It's a logic flaw in the kernel's crypto code (authencesn via AF_ALG and splice()) that allows a small write into the page cache, which can be used to tamper with a setuid binary like /usr/bin/su. Think how bad this is going to be for shared environments like Kubernetes, CI runners, and cloud sandboxes, where it enables container escape and tenant-to-host compromise. Found by Theori's Xint Code scanner, patched in the mainline kernel, and publicly disclosed on April 29, 2026; if you can't patch right away, the recommended workaround is to disable the algif_aead module.