Event ID 5723 Source: NETLOGON

Evening experts,

We have a number of instances of Event ID 5723 Source: NETLOGON on one of our DC's with Win Svr 2008 installed (see below). Although the pc in the event does not belong to our network and never did. I work for a financial organisation and security is as tight as it can be regarding physical access to our main office so I'm assuming this access attempt was made remotely. Please, can you help me out here on how this could have happened? We don't have wifi on our network so I'm a little baffled here. Please advise.  

event id
wcgplcAsked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

x
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Scott SilvaNetwork AdministratorCommented:
Whatever it is, it got far enough into your network to try to login to the domain... You might need to do a system wide network audit to make sure someone didn't plug something into an open port OR has a virtual machine going...
Turning netlogin debugging on should capture IP addresses and maybe help you track down what is happening...

https://support.microsoft.com/en-us/help/109626/enabling-debug-logging-for-the-netlogon-service

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Windows Server 2008

From novice to tech pro — start learning today.