January 2023 Exchange Server Security Updates

Andres Bohren

2023-01-10

Hi All,

Just a few hours Ago the January 2023 Exchange Server Security Updates have been released.

Released: January 2023 Exchange Server Security Updates

https://techcommunity.microsoft.com/t5/exchange-team-blog/released-january-2023-exchange-server-security-updates/ba-p/3711808

In my case i have downloaded the Security Update 5 for Exchange 2016 CU23

Security Update For Exchange Server 2016 CU23 SU5 (KB5022143)

https://www.microsoft.com/en-us/download/details.aspx?id=104914

Then run the Security Update

When you run the HealthChecker and it has found an update close and reopen Exchange Management Shell after the update.

Exchange HealthChecker

https://microsoft.github.io/CSS-Exchange/Diagnostics/HealthChecker/

.\HealthChecker.ps1

As you can see the "SerializedDataSigning" is not enabled

Let's run the MonitorExchangeAuthCertificate - basically just checks if the Certificate is still valid or needs to be renewed.

I've blogged how to do that.

Renew Microsoft Exchange Server Auth certificate

https://blog.icewolf.ch/archive/2021/06/26/renew-microsoft-exchange-server-auth-certificate.aspx

MonitorExchangeAuthCertificate - Microsoft - CSS-Exchange

.\MonitorExchangeAuthCertificate.ps1

In that case i can Enable the SigningVerification

SerializedDataSigningCheck - Microsoft - CSS-Exchange

Organizational-wide:

New-SettingOverride -Name "EnableSigningVerification" -Component Data -Section EnableSerializationDataSigning -Parameters @("Enabled=true") -Reason "Enabling Signing Verification"

Get-ExchangeDiagnosticInfo -Process Microsoft.Exchange.Directory.TopologyService -Component VariantConfiguration -Argument Refresh

Let's run the HealthChecker again

.\HealthChecker.ps1

Regards

Andres Bohren

Works as a Microsoft Cloud Engineer/Architect for midsize to large Enterprises. He has a special focus on M365 including Identity, Messaging, Communication, Security and PowerShell but also Azure Technologies. He is Co-Organisator of the <Microsoft 365 Community Schweiz> Meetup group and was Speaker at several other Meetups.