Huawei has released the details of the April 2020 security patch. It includes fixes for the EMUI and Magic UI. In addition, the security patch also includes the fixes from Google in its Android OS. You can find out the details of the bugs at the Huaweicentral.com.
EMUI 10.1 and Magic UI 3.1 List: These Huawei and Honor smartphones are eligible for next big update
Below you can see the list of bug fixes:
The update fixes 5 critical issues and several high-risk issues. There was no medium and low-level issue fixed in this patch. The company has already fixed several critical and high-risk issues in the March 2020 security patch.
For more information on security patches, you can also see the Android security bulletins (https://source.android.com/security/bulletin).