CVE-2026-49481

CRITICAL CVSS 3.1: 9.6
Updated Aug 13, 2026
Linux
Parameter Value
CVSS 9.6 (CRITICAL)
Affected Versions before 5.4.0
Type CWE-78 (OS Command Injection)
Vendor Linux
Public PoC No

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.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
None
No disruption

CVSS Vector v3.1

Weakness Type (CWE)