RTAC86U How to block port 445

[BobD]

I read today about a Win 10 bug which may lead to an exploit eventually. One of the fixes was to block port 445 on the router. I had a look and I couldn't work out how to block a port on my router. Can someone more knowledgeable advise me.

My router RT-AC86U is running standard ASUS firmware at the latest level I can find at 3.0.0.384_81352

This is a link to the Microsoft advisory
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/adv200005

 

[dave14305]

Everything from the internet is blocked by default unless you explicitly allow it via port forwarding, DMZ or custom rules.

 

[ColinTaylor]

This vulnerability would have to be exploited by a client that is already connected to your LAN (think - virus infected PC on a business network). This is not something that could be exploited from the internet.

 

[BobD]

Thanks guys. Your advice has reassured me. There is also a PowerShell temporary fix as outlined in the Microsoft document. I have implemented that on my machines. I also ran a port scanner from Gibson Research on the router and all ports were reported as stealth and not responding to a probe.