Samsung Knox
Samsung Knox is a mobile device management and trusted computing framework pre-installed on most Samsung mobile devices, and implements ARM TrustZone in hardware. It allows the management of work devices, such as employee mobile phones, interactive kiosks, and barcode scanners. Like other MDMs, Knox allows organizations to control a device's pre-loaded applications, settings, boot-up animations, home screens, and lock screens.
Overview
Knox provides trusted computing and mobile device management features. Knox's hardware is based on an implementation of ARM TrustZone, a bootloader ROM, and secure boot. These trusted computing environments are used to store sensitive data, like cryptographic materials and certificates.MDM allow businesses to customize their devices for their needs. IT administrators can register new devices, identify a unified endpoint management system, define the organizational rules that govern the use of devices, and upgrade device firmware over-the-air. Knox's MDM services are registered and accessed through the web, APIs, or proprietary SDKs.
A few Samsung devices with Knox were approved for US governmental use in 2014, as long as they're not used to store classified data.
Since Android 8, Knox is used to prevent root access to apps even after a successful rooting.
In October 2014, a security researcher discovered that Samsung Knox stores PINs in plain text rather than storing salted and hashed PINs and processing them by obfuscated code.
In May 2016, Israeli researchers Uri Kanonov and Avishai Wool found three vulnerabilities in specific versions of Knox.
Several security flaws were discovered in Knox in 2017 by Project Zero.
e-Fuse
Samsung Knox devices use an e-fuse to indicate whether or not an "untrusted" boot path has ever been run. The e-Fuse will be set in any of the following cases:- The device boots with a non-Samsung signed bootloader, kernel, kernel initialization script, or data.
- The device is rooted.
- Custom firmware is detected on the device.