Microsoft has made an essential change to its Excel spreadsheet software program (opens in new tab) which ought to make it safer for customers worldwide.

In the summertime of 2022, Microsoft determined to lastly put a cease to the abuse of macros in Workplace recordsdata, which had been extensively used to deploy malware to focus on endpoints, prompting Microsoft to dam all macros in Workplace recordsdata downloaded from the web.

Since then, hackers began experimenting with various strategies to ship numerous malware payloads, and one methodology grew fashionable – XLL add-ins. 

Rolling out the characteristic

XLL recordsdata are basically DLLs Excel customers can add to develop this system’s functionalities with issues like dialog containers, customized features, or toolbars. As such, they offered the subsequent greatest approach to deploy malware, after macros. 

Now, in a brand new announcement, Microsoft mentioned Excel is obstructing all untrusted XLL add-ins by default in Microsoft 365 tenants worldwide.

The change was first introduced in early January this 12 months, when the corporate added it to the Microsoft 365 roadmap and rolled it out to Insiders for testing.

Right now, two months later, it’s rolling the characteristic out to all different customers. By late March, all desktop customers within the Present, Month-to-month Enterprise, and Semi-Annual Enterprise channels, ought to get this further layer of safety.

“We’re introducing a default change for Excel Home windows desktop apps that run XLL add-ins: XLL add-ins from untrusted places will now be blocked by default,” Microsoft mentioned. “We have now already accomplished rolling out to Insiders preview. We’ll start rolling out early March and count on to finish by late March.”

As soon as the change is full, customers shall be notified when attempting to run XLL-powered content material coming in from an untrusted location. The notification will clarify what the potential dangers are, and share extra data on how to ensure customers keep secure.

As soon as the replace rolls out, it’s secure to imagine that delivering malware with shortcut recordsdata (.LNK) will develop into much more fashionable. 

• These are the perfect firewalls (opens in new tab) in the present day

By way of: BleepingComputer (opens in new tab)