Moonlight Game Streaming Client Vulnerable to Remote Code Execution

CVSScvssV3_1: 8.8

Moonlight is an open source implementation of NVIDIA’s GameStream protocol that allows game streaming from GeForce Experience to other devices. A vulnerability has been discovered in Moonlight’s common code library called Moonlight-common-c that could allow remote code execution on clients.

The vulnerability is a buffer overflow issue caused by improper bounds checking of user input. Buffer overflows happen when a program tries to write more data into a fixed-size buffer than it can hold. This can overwrite adjacent memory and corrupt the program in dangerous ways.

A malicious game streaming server could potentially exploit this vulnerability by sending specially crafted data to crash the Moonlight client or even execute arbitrary code on the client device with the user’s privileges. This would give an attacker full control of the targeted system.

To protect yourself, users should update their Moonlight installation to the latest version which has addressed this vulnerability. Regularly applying software updates is important as it patches security issues. Users should also use firewalls to limit incoming connections and only stream games from trusted servers.

While concerning, responsible disclosure of this vulnerability to the developers helped get it resolved quickly. Staying vigilant about application updates helps keep users and their devices secure.