Warning: Copy Fail, Getting Root on Major Linux Distributions, Patch Immediately!

CVE-2026-31431 is a Linux kernel privilege-escalation vulnerability that allows local attackers to modify the in-memory page cache of files to inject and execute code in privileged processes, enabling root compromise and potential container escapes; the exploit is small, reliable, widely portable across major distributions, and is reported as actively exploited, so immediate kernel patching and mitigations (disable algif_aead or block AF_ALG via seccomp) and enhanced monitoring are recommended.