Samsung Message Guard

Samsung Message Guard is an advanced feature which prevents zero-click attacks on messaging applications. This feature is included as part of Samsung Auto Blocker, and is enabled by default for all Galaxy devices running One UI 6.0 and higher.

Messaging apps contain various permissions, ranging from access to common utilities such as photo gallery and calendar to more sensitive utilities such as files, microphone, and camera. So, when an attacker compromises these apps, the damage can be catastrophic. Samsung Message Guard is used to mitigate these types of attacks on messaging apps.

Whenever an image file arrives via text, it is trapped and isolated from the rest of your device. This prevents malicious code from accessing your phone’s files or interacting with its operating system. Samsung Message Guard checks the image file bit by bit and processes it in a controlled environment or sandbox, ensuring it cannot infect the rest of your device. It runs in the background and doesn’t need any activation by the user.

To ensure defense in depth against threats, the following security principles are applied:

• Broad coverage: All image files received via messaging apps are considered untrusted data.

• Never-trust: All untrusted data received is isolated from the system. For isolation, the image decoders are separated from the messaging app. Thus, mitigating any vulnerabilities in parsing & decoding functions.

• On by default: All messaging apps are supported, without the need of any additional integrations.