Yes, it is an IM.
Sorry, I assume that you have learnt it from chinese avast! users.
The laws of China have not covered all the sides of the software industry, so many software editors have been very remiss in fulfilling their obligations. That's why I'm not surprised at potentially malicious code and fatal bugs in QQ.
How to deal with QQ? If trust it without reservation, these potentially malicious code and fatal bugs will possibly hurt users' benefit; if treat it strictly, there will be endless so-called "false positives" and most newbies will only blame the trouble on antivirus softwares. It is just a dilemma with Chinese characteristics.
The same question arises in Thunder, a popular chinese download manager. Thunder will collect privacy information of users, but most users still use it and blame conscientious antivirus softwares for "false positives".
PS: QQ has not opened its message transport protocol. In fact, Tencent tries hard to prevent QQ users from using any third-party clients, such as Pidgin, LumaQQ, etc. The narrow idea also prevents avast! IM shield from protecting QQ chat.