Hot Take Microsoft App Control short test

Microsoft Defender
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Parkinsond

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I have applied MAC without adding any exclusions to Program Files or Windows folders.

Surprisingly, CrystalDiskInfo, OnlyOffice, and Potplayer were blocked, inspite of the presence of digital signature of their installers, not only that, but also of the blocked exe and dll files inside Program Files folder.
Meanwhile, 7-zip, lacking digital signature of both installer and components in Program Files folder, launched with no problem.

It looks ISG relies more on reputation (especially how frequent the program is used) than digital signature.
 
I have applied MAC without adding any exclusions to Program Files or Windows folders.

Surprisingly, CrystalDiskInfo, OnlyOffice, and Potplayer were blocked, inspite of the presence of digital signature of their installers, not only that, but also of the blocked exe and dll files inside Program Files folder.
Meanwhile, 7-zip, lacking digital signature of both installer and components in Program Files folder, launched with no problem.

It looks ISG relies more on reputation (especially how frequent the program is used) than digital signature.
That's an interesting observation, Parkinsond. I've seen similar behaviors with various security tools that incorporate cloud-based reputation systems—it's not uncommon for them to weigh factors like usage frequency, community reports, and behavioral analysis more heavily than just a digital signature alone. Signatures can help verify authenticity, but if a file is rare or hasn't built up a strong "known good" reputation, it might still get flagged or blocked as a precaution.

In the case of 7-Zip, its widespread use and long history probably give it a solid rep in most databases, even without signatures on every component. For the others you mentioned, adding manual exclusions (if you're comfortable) or reporting them as false positives to the vendor could help refine their detection. Just be cautious with exclusions to avoid weakening your overall protection.

Have you checked the logs for specific reasons why those were blocked? That might give more clues.
 
Surprisingly, CrystalDiskInfo, OnlyOffice, and Potplayer were blocked
That is "funny', considering that CrystalDiskInfo and Potplayer are also distributed via MS Store, thus verified by MS. Stupid App Control never seizes to amaze me.
 

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WDAC ISG manages files with MotW differently from files with no MotW. In the first case, the positive WDAC reputation is taken from SmartScreen.
 
WDAC ISG manages files with MotW differently from files with no MotW. In the first case, the positive WDAC reputation is taken from SmartScreen.
After launching the installer, it has lost motw.

Capture.PNG
Would you like to try executing it again?
 
WDAC ISG manages files with MotW differently from files with no MotW. In the first case, the positive WDAC reputation is taken from SmartScreen.
I have tried one more program; downloaded Minimal firewall installer.

It was blocked by SmartScreen; after manually removing MoTW, it was blocked again but this time with WDAC.
 

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