Exploit Released for Unpatched Ubuntu Linux Flaw Enabling Host-Root Container Escape

DepthFirst released proof-of-concept code for CVE-2026-80521, a Linux Kernel AF_UNIX socket use-after-free that can let a containerized attacker obtain root access on the host. Ubuntu 26.04, 24.04, and 22.04 LTS remain unpatched, including newer kernel packages used for AWS, Azure, and GCP workloads. The upstream Linux Kernel fix is available, but Ubuntu lists the issue as work in progress; no confirmed in-the-wild exploitation has been reported.