CVE-2026-49481
CriticalCVSS 9.6Summary
UpSnap before 5.4.0 has an OS command injection vulnerability in device management due to unsafe shell command template interpolation using the ip and mac fields. User-controlled values can be inserted into wake_cmd and shutdown_cmd templates and executed without sanitization, resulting in authenticated RCE. A low-privileged user with permission to create or edit devices can execute arbitrary OS commands on the UpSnap server.
Risk Assessment
An authenticated attacker with low privileges can take over the UpSnap server, potentially leading to full compromise and access to sensitive data.
Recommendation
Update UpSnap to version 5.4.0 or later, which includes the fix.
Original NVD description (English source)
UpSnap is a wake on lan web app. Versions prior to 5.4.0 have an OS command injection vulnerability in the UpSnap’s device management functionality due to the presence of unsafe shell command template interpolation using the ip and the mac fields. User-controlled values can be inserted into the wake_cmd and shutdown_cmd templates and executed via /bin/sh -c (Linux) or cmd /C (Windows) without sanitization, resulting in an authenticated Remote Code Execution (RCE). A low-privileged user with permission to create or edit devices can execute arbitrary operating system commands on the UpSnap hosted server. Version 5.4.0 patches the issue.