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Hackers Are Using a New Microsoft SharePoint Flaw

SecurityWeek covered this vulnerability on Sep 27, 2026. Below is a plain-English breakdown of what it is, how it actually works, and whether it matters, written for people who are curious about hacking and security but don't have a technical background.

SecurityWeek · Sep 27, 2026

In plain words

Imagine you have a door with a lock, but someone found a way to pick that lock easily. This is similar to what is happening with a bug in Microsoft SharePoint¹. It is like a special key that can open the door without the real key.

What's broken

The bug is called CVE-2026-65660², which is a way to say a specific problem in the code of Microsoft SharePoint. An attacker can use this bug to do things they should not be able to do, like getting into areas they should not have access to.

How it actually works

Here is how it works: an attacker sends a special message to the Microsoft SharePoint server, which has the bug. Because of the bug, the server does what the attacker wants, instead of saying no. This is like the lock picking example, where the special message is like the lock pick.

Proof of concept

There is a proof of concept, or PoC³, which is like a demonstration that the bug is real and can be used. This means that the bug is not just theoretical, but actually works. However, it is not clear from the source how mature this PoC is.

Is it real

The bug is being used in real attacks, which means hackers are actively trying to use it to break into systems. It is not clear how long this has been happening, but it is a concern because it means the bug is being used in the wild. One limiting factor could be that some features might be off by default, but this is not specified.

What to do

To fix the bug, you should patch your Microsoft SharePoint system. This is like replacing the lock with a new, better one that the attackers cannot pick. The US government is telling its agencies to patch by September 28.

Terms

¹ Microsoft SharePoint
, a type of software that helps teams work together on documents and projects
² CVE-2026-65660
, a unique number given to a specific problem in computer code
³ PoC
, a demonstration that a bug is real and can be used

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About this explainer

KeepLooped tracks the newest offensive-security tools, techniques, vulnerabilities and research from 80+ trusted sources and turns the most important items into plain-language explainers, so people learning security can keep up without a technical background. This page summarises and explains the source linked below; it was produced with AI assistance and is meant as a beginner-friendly starting point. Always confirm specifics, versions, CVE details, and exploitation status, against the original source and official advisories. Curated and published by HackproofHacks.