CVE-2026-3888

A high-severity local privilege escalation vulnerability, CVE-2026-8933, exists in the snap-confine component of default Ubuntu Desktop installations (24.04, 25.10, 26.04), allowing unprivileged users to gain root access. The flaw arises from a race condition during sandbox initialization, enabling attackers to manipulate temporary file ownership and permissions. By exploiting symbolic links and FUSE file systems, an attacker can write malicious rules to sensitive system paths and achieve arbitrary code execution as root.