Please help to identify the following description belonging to which technique in MITRE and the corresponding tactics: Ke3chang has dropped their malware into legitimate installed software paths including: `C:\ProgramFiles\Realtek\Audio\HDA\AERTSr.exe`, `C:\Program Files (x86)\Foxit Software\Foxit Reader\FoxitRdr64.exe`, `C:\Program Files (x86)\Adobe\Flash Player\AddIns\airappinstaller\airappinstall.exe`, and `C:\Program Files (x86)\Adobe\Acrobat Reader DC\Reader\AcroRd64.exe`.