Adversaries may modify system software binaries to establish persistent access to devices. System software binaries are used by the underlying operating system and users over adb or terminal emulators.
Adversaries may make modifications to client software binaries to carry out malicious tasks when those binaries are executed. For example, malware may come with a pre-compiled malicious binary intended to overwrite the genuine one on the device. Since these binaries may be routinely executed by the system or user, the adversary can leverage this for persistent access to the device.
|S0316||Pegasus for Android|
|S0289||Pegasus for iOS|
Device attestation could detect devices with unauthorized or unsafe modifications.
A locked bootloader could prevent unauthorized modifications of protected operating system files.
Security updates frequently contain fixes for vulnerabilities that could be leveraged to modify protected operating system files.
|M1004||System Partition Integrity||
Android includes system partition integrity mechanisms that could detect unauthorized modifications.
Verified Boot can detect unauthorized modifications to the system partition. Android’s SafetyNet API provides remote attestation capabilities, which could potentially be used to identify and respond to compromised devices. Samsung Knox provides a similar remote attestation capability on supported Samsung devices. Application vetting services could detect applications trying to modify files in protected parts of the operating system.