Microsoft uses a multipronged approach to help its customers manage their risks. This approach includes three key elements: It is impossible to completely prevent vulnerabilities from being introduced during the development of large-scale software projects. As long as human beings write software code, no software is perfect and mistakes that lead to imperfections in software will be made. Some imperfections (“bugs”) simply prevent the software from functioning exactly as intended, but other bugs may present vulnerabilities. Not all vulnerabilities are equal; some vulnerabilities won’t be exploitable because specific mitigations prevent attackers from using them. Nevertheless, some percentage of the vulnerabilities that exist in a given piece of software poses the potential to be exploitable.

How does Microsoft identify Malware & PUPs

The four major basis or criteria for classifications by Microsoft uses are: Some of the software is not necessarily harmful, but it does spoil Windows experience. They do it by either installing applications without user knowledge or serve advertisements without consent.

1] Malicious software

These are applications and software which compromise user security. They can steal your personal information, credit card information, and even lock down your files. The last one is called Ransomware, which is one of the worst forms of malware we have seen in recent years.  It is one of the reasons why Windows Security introduced Controller Folder Access and OneDrive Personal Vault. Here is the list of methods or process Microsoft classifies to identify the software as a Malware:

BackdoorDownloaderDropperExploitHacktoolMacro virusObfuscatorPassword stealerRansomwareRogue security softwareTrojanTrojan clickerWorm.

2] Unwanted software

These are the software that disrupts your Windows experience. According to Microsoft, software should keep the user in control, and not the other way round. Depending on the behavior, Microsoft can identify and then warn the user about any Unwanted Applications that fall into these categories.

Lack of choiceLack of controlInstallation and removalAdvertising and advertisements.

Lack of choice A software without clear intent, transfer data in the background, installs or removes software, hides from users fall into this category. Microsoft also classifies unwanted software if it triggers false alarms about your device’s health or asks for payment to fix it. There are tons of software that claim to speed up your computer. They do it by creating false claims and then offer you to buy the pro version to fix it. Lack of control Any software which takes over browser experience, change search settings, redirect web traffic without consent, or modify the content without user consent. We have seen a lot of software which used to change the default search engine or install toolbars during installation. Probably one of the most annoying problems. Poor Installation and Uninstallation Experience Some apps do not entirely uninstall even when you manually uninstall them. They leave behind programs that keep doing something rouge to the system. Some of them try their best not to get uninstalled by either hiding from Add/Remove programs or misleading prompts or pop-ups when you try to uninstall it. Advertising and advertisements While it is ok to advertise, but it should take user consent. Some apps advertise their inhouse software or third party software to make money. The worst part is that they make you click such an advertisement either by downloading files or opening a webpage. They even block the entire view, and the chances are that you will never find a close button for such advertisements.

3] Consumer Feedback

If you see or experience such software, you can always submit a software for analysis.  Microsoft also uses Windows Security in conjunction with this making it easy for consumers to report about such applications. If a lot of users report a software a lot of times, it raises a red flag. A classic example is CCleaner. At one point in time, it was a must-have application for all Windows users. Later many users reported that the utility could not be recommended anymore. Microsoft Answers blacklisted CCleaner links.

4] Potentially unwanted application (PUA)

Potentially Unwanted Applications are not malware, but Microsoft blocks download of any application or software that falls into the above categories and more. PUAs are those applications which show the following behaviors or fall into these categories:

AdvertisingTorrentCryptominingBundlingMarketingEvasionPoor industry reputation.

I hope the post helped you to understand what it takes for Microsoft or probably any security company to identify malware and potentially unwanted applications.

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