Audio driver supplied by Conexant may put PCs from other makers at risk, too.
HP is selling more than two dozen models of laptops and tablets that covertly monitor every keystroke a user makes, security researchers warned Thursday. The devices then store the key presses in an unencrypted file on the hard drive.
The keylogger is included in a device driver developed by Conexant, a manufacturer of audio chips that are included in the vulnerable HP devices. That’s according to an advisory published by modzero, a Switzerland-based security consulting firm. One of the device driver components is MicTray64.exe, an executable file that allows the driver to respond when a user presses special keys. It turns out that the file sends all keystrokes to a debugging interface or writes them to a log file available on the computer’s C drive.
“This type of debugging turns the audio driver effectively into keylogging spyware,” modzero researchers wrote. “On the basis of meta-information of the files, this keylogger has already existed on HP computers since at least Christmas 2015.”
The log file—located at C:\Users\Public\MicTray.log—is overwritten after each computer reboot, but there are several ways that the contents could survive for weeks, or even indefinitely. Forensic tools make restoring deleted or overwritten files easy. And in the event the computer is backed up regularly, the backups would contain a comprehensive history of everything that was typed on the keyboard—including passwords, e-mails, and contacts. Modzero researchers said they issued the public advisory after both HP and Conexant failed to respond to messages privately reporting the findings.
In technical details that accompanied Thursday’s advisory, the modzero researchers added: