What’s AM_Delta_Patch_1.443.825.0.exe (Microsoft Antimalware WU Stub)? Is it safe or a virus?

The executable file "AM_Delta_Patch_1.443.825.0.exe" by Microsoft Corporation, described as "Microsoft Antimalware WU Stub," is used to deliver incremental updates to Microsoft’s antimalware definitions through Windows Update. It applies only the changes needed to bring existing definitions up to the latest version, reducing the size of updates and improving update efficiency.

Below are 4 simple steps you can take to see if the AM_Delta_Patch_1.443.825.0.exe process is safe or malware.

Researched by Carl @ SpyShelter Labs

Download AppControl Free

More about AM_Delta_Patch_1.443.825.0.exe on WINDOWS

Who makes AM_Delta_Patch_1.443.825.0.exe (Microsoft Antimalware WU Stub)?

We’ve found Microsoft Corporation should be the publisher of AM_Delta_Patch_1.443.825.0.exe.

How do we know? Our SpyShelter cybersecurity labs focuses on monitoring different types of Windows PC executables and their behaviors for our popular SpyShelter Antispyware software. Learn more about us, and how our cybersecurity team studies Windows PC executables/processes.

What does it mean if someone is the publisher of a PC .exe (executable or process)?

The publisher of an executable is the entity responsible for its distribution and authenticity. Most processes/executables on your PC should be signed. The signature on the executable should have been verified through a third party whose job it is to make sure the entity is who it says it is. Find an unsigned executable? You should consider scanning any completely unsigned .exe on your PC.

Last updated: January 24, 2026

Curious about other processes on your PC?
Try SpyShelter or search below.

Or browse the process directory by name:

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z #

Why should you trust us?

Our team at SpyShelter has been studying Windows PC executables for over 15 years, to help fight against spyware, malware, and other threats. SpyShelter has been featured in publications like The Register, PC Magazine, and many others. Now we’re working to share free, actionable, and easy to understand information about Windows executables (processes) with the world, to help as many people as possible keep their devices safe. Learn more about us on our "About SpyShelter” page.

Have any questions? Please join our free public SpyShelter PC Security Forum and talk cybersecurity with our USA-based team. We love talking about PC Security and we’d like to get to know you.