The most reliable source is the developer’s GitHub repository.
Downloading an updated (UPD) ADB & Fastboot package as an Android NDK-based Magisk module is the safest, most flexible method for keeping these critical tools current on rooted Android devices. It bypasses system partition restrictions, provides root-level functionality, and allows easy rollback. Users are advised to obtain modules only from trusted sources (e.g., verified GitHub repos) and to verify binary integrity via SHA checksums.