"Over the past few years, we’ve seen some high profile security problems with laptops from Lenovo, Samsung, and Dell. HP, up until now, had managed to escape any serious issues. According to the Swiss infosec company ModZero, that’s changed, courtesy of a keylogger embedded (probably accidentally) into certain audio drivers used on HP laptops."
HP uses Conexant audio chips for some of its laptops, which means it also ships Conexant’s included software and drivers. Here’s how ModZero describes the problem: