ethtool is a Linux command-line utility for inspecting and changing settings exposed by network interface drivers. Administrators commonly use it to check link status, supported speeds, device capabilities, and driver information, or to adjust supported options. It operates from user space, communicating with the kernel’s network-device and driver interfaces.
In cybersecurity, ethtool matters because requests made through it can exercise kernel driver code. In the Linux virt_wifi issue described in this context, an ethtool-related path could reach code affected by a use-after-free. The utility itself is not the vulnerability: the risk lies in how the kernel handles a request for a particular device. Defenders should keep kernel packages patched and restrict access to privileged network-device changes where appropriate.