根据卡饭论坛上网友的观点，自诺顿360 V24版本之后的扫描引擎改为了Avast，笔者进行了一番搜索，找到了一些证据。
并且在新版V24中削弱了SONAR、IPS和反垃圾邮件功能。有网友从Win 98、2000年就开始用诺顿了，这次大改版之后，这些忠实的用户也随之感到失望。
Why does Norton have changed their product to AVAST Antivir Engine?
https://malwaretips.com/threads/anyone-tried-norton-v24.131066/
One Less Scanner? Norton Antivirus Jumps on Avast's Engine
https://hackerdose.com/security/norton-jumps-on-avasts-engine/
Norton setzt auf Avast-Scan-Engine
https://www.heise.de/news/Norton-setzt-auf-Avast-Scan-Engine-9866036.html
AV-Comparatives 维护着一份防病毒软件使用哪种扫描引擎的列表
上面记录着AVG和Norton的第三方引擎是Avast
https://www.av-comparatives.org/list-of-consumer-av-vendors-pc/
Norton with avast engine
https://community.norton.com/t/norton-with-avast-engine/370204
Norton silently becoming Avast!?
https://community.avast.com/t/norton-silently-becoming-avast/848184