A billion or more Android devices are vulnerable to hacks that can turn them into spying tools by exploiting more than 400 vulnerabilities in Qualcomm’s Snapdragon chip, researchers reported this week.

The vulnerabilities can be exploited when a target downloads a video or other content that’s rendered by the chip. Targets can also be attacked by installing malicious apps that require no permissions at all.

From there, attackers can monitor locations and listen to nearby audio in real time and exfiltrate photos and videos. Exploits also make it possible to render the phone completely unresponsive. Infections can be hidden from the operating system in a way that makes disinfecting difficult.