Samsung is accelerating the release of the October 2025 security patch for a series of Galaxy devices before the end of the month, and the Galaxy S21 FE is the latest name to be added. The update has now started rolling out in Vietnam, before expanding to other markets in the near future.

According to recorded information, the Galaxy S21 FE has received the update with firmware code G990EXXSJHYJ4, about 268 MB in size. The device is now in the quarterly security update group, which means it will receive four patches per year instead of monthly updates as before. Users can download it by going to Settings > Software update > Download and install, then restarting the device to complete the process.

The new patch helps the Galaxy S21 FE to be better protected against the latest security vulnerabilities. According to Samsung's documentation, the October update includes 14 critical patches from the Android operating system and 20 Samsung-specific patches (SVE). One of the important bugs fixed is in Samsung DeX, preventing attackers from accessing the list of recent applications. In addition, the patch also improves security in KnoxGuard, Knox Enterprise, contacts, and fingerprint sensors.

Previously, Samsung started deploying One UI 8 based on Android 16 for Galaxy S21 FE in some regions, but this update is still being distributed gradually. The One UI 8 version comes with the September 2025 security patch, so users can check and install the October 2025 patch after updating to achieve the highest level of security for their devices.

According to the roadmap, the Galaxy S21 FE - the Fan Edition model launched in 2022 - will likely be upgraded to One UI 8.5 next year, bringing many performance improvements and new generation AI features to users.