ASUS Security Diagnostic Tool is a free, portable app from Asus to check your computer for the Shadowhammer Malware.

More information from Asus:

How do I know whether or not the malware attack has targeted my device?
Only a very small number of specific user group were found to have been targeted by this attack, and as such, it is extremely unlikely that your device has been targeted. However, if you are still concerned about this matter, feel free to use ASUS’ security diagnostic tool or contact ASUS Customer Service for assistance.

What should I do if my device is affected?
Immediately run a backup of your files and restore your operating system to factory settings. This will completely remove the malware from your computer. To ensure the security of your information, ASUS recommends that you regularly update your passwords.

How do I make sure that I have the latest version of ASUS Live Update?
You can find out whether or not you have the latest version of ASUS Live Update by following the instructions shown in the link below:
https://www.asus.com/support/FAQ/1018727/.

Have other ASUS devices been affected by the malware attack?
No, only the version of Live Update used for notebooks has been affected. All other devices remain unaffected.