#adware

The malware did not disable your antivirus. You did, to stop it complaining about the wallpaper app

ValleyRAT is hiding inside QN Wallpaper, a genuine signed Chinese desktop app that bundles adware. Because the adware trips antivirus, users add it to the exclusion list — and the backdoor rides in through the hole they made. Kaspersky counted over 100,000 detections across 1,500-plus users, mostly in China and India.