Advice Request Excel is trying to connect through port 53

[czesetfan]

Is it a good idea to enable outbound connection to port 53 for Excel ?
Why is this happening?

 

[Kongo]

Is it a good idea to enable outbound connection to port 53 for Excel ?
Why is this happening?

Take a look at this tool. Might be interesting for you. You can also block outbound connections for Office applications.

FirewallHardening tool | MalwareTips

FIREWALLHARDENING (new ver. 3.0.0.1, July 2024) FirewallHardening is a part of the Hard_Configurator project and can be used also as a standalone...

malwaretips.com

 

[silversurfer]

Is it a good idea to enable outbound connection to port 53 for Excel ?
Why is this happening?

Just take a look on this link below, explanation of Firewall port numbers.

Port 53: Domain Name System (DNS)

List of TCP and UDP port numbers - Wikipedia

en.wikipedia.org

Should be no problem to block outbound connection for Excel unless it's required for certain functions of Excel, but that you will see when something with Excel doesn't work as it should...

 

[czesetfan]

Thank you for your quick responses.
I'm rather interested in why Excel is trying to communicate on port 53. Does it need it for anything? It works normally even if I block it, so I guess it's not necessary.

 

[ItsReallyMe]

Take a look at this tool. Might be interesting for you. You can also block outbound connections for Office applications.

FirewallHardening tool | MalwareTips

FIREWALLHARDENING (new ver. 3.0.0.1, July 2024) FirewallHardening is a part of the Hard_Configurator project and can be used also as a standalone...

malwaretips.com

is this only work if we use windows firewal, what if we have comodo firewall or kaspersky firewall?

 

[Kongo]

is this only work if we use windows firewal, what if we have comodo firewall or kaspersky firewall?

This is only for the Windows Firewall. If you are using Comodo or Kaspersky you need to add those rules manually.

 

[czesetfan]

Coming back to the topic. Does anyone know why Excel needs to connect via port 53?
It gets its DNS information from the OS, doesn't it?