エンジニア。B2Bコンサル。基本はVPNとQNAPでリモートワーク。自由な時間を得る代わりに、顧客先からなど毎週の技術的な課題に学ぶ日々。最近は製造業系IoT機械。クラウドDB x API x 機械制御。dockerやHAproxyでLBやリバースプロキシ作ったり。Node-REDとC++を使い分けるのが好み。
‼️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: https://t.co/f5G6KnEv35
Write-up: https://t.co/W86Pz2PC6C
GitHub: https://t.co/zAMTC6nTRk
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.