Security Updates Exchange 2013-2019 (Nov2022)

Posted on November 8, 2022 by Michel de Rooij

The Exchange product group released November updates for Exchange Server 2013, 2016 and 2019. Note that these Security Updates address the vulnerabilities CVE-2022-41040 and CVE-2022-41082 that were reported end of September. More on those in an earlier post.

Note: You can keep the current URLScan mitigations in-place, and remove them after installing these security updates at your convenience. The recommendation to disable Remote PowerShell for non-admins is upheld, but this is best practice regardless.

The vulnerabilities addressed in these Security Updates are:

Vulnerability	Category	Severity	Rating
CVE-2022-41040	Elevation of Privilege	Critical	CVSS:3.1 8.8 / 7.9
CVE-2022-41082	Elevation of Privilege	Important	CVSS:3.1 8.8 / 8.3
CVE-2022-41078	Elevation of Privilege	Important	CVSS:3.1 8.0 / 7.0
CVE-2022-41123	Elevation of Privilege	Important	CVSS:3.1 7.8 / 6.8
CVE-2022-41079	Elevation of Privilege	Important	CVSS:3.1 8.0 / 7.0
CVE-2022-41080	Elevation of Privilege	Critical	CVSS:3.1 8.8 / 7.7

The following Security Updates address these vulnerability for the Exchange builds mentioned, with the exception of CVE-2022-41123 which does not apply to Exchange Server 2013:

Exchange	Download	Build	KB	Supersedes
Exchange 2019 CU12	Download	15.2.1118.20	KB5019758	KB5019077
Exchange 2019 CU11	Download	15.2.986.36	KB5019758	KB5019077
Exchange 2016 CU23	Download	15.1.2507.16	KB5019758	KB5019077
Exchange 2016 CU22	Download	15.1.2375.37	KB5019758	KB5019077
Exchange 2013 CU23	Download	15.0.1497.44	KB5019758	KB5019076

In case you missed it, per the Security Updates of August, you can enable Windows Extended Protection for increased protection against certain vulnerabilities. More information this process and its requirements can be found in the post on the August updates here.

Security updates are Cumulative Update level specific. You cannot apply the update for Exchange 2019 CU12 to Exchange 2019 CU11. Also, the security update download has the same name for different Cumulative Updates, and I would suggest tagging the file name with the CU level, e.g. Exchange2019-CU12-KBXXXXXX-x64-en.msp.

Exchange servers running as part of hybrid deployment are running services, and thus need to be included in the patch cycle. If you are running Exchange 2019 CU12 Management Tools-only (for recipient management), you do not need to deploy this SU.

On a final note, as with any patch or update, I’d recommend to apply this in a test environment first, prior to implementing it in production. However, it is not recommended to wait for regular maintenance cycles when it concerns security updates, and follow a more agile approach; the ratings are an indication of the urgency.

Security Updates Exchange 2013-2019 (Oct2022)

Posted on October 11, 2022 by Michel de Rooij

The Exchange product group released October updates for Exchange Server 2013, 2016 and 2019. Note that these Security Updates do NOT address the vulnerabilities CVE-2022-41040 and CVE-2022-41082 that have been reported on since end of September. For now, mitigate those by follow the instructions mentioned an earlier post here.

The vulnerabilities addressed in these Security Updates are mostly the same as the ones addressed by the Security Updates of August, with the exception of CVE-2022-34692. Also, the CVSS rating of CVE-2022-30134 has been adjusted:

Vulnerability	Category	Severity	Rating
CVE-2022-21979	Information Disclosure	Important	CVSS:3.1 4.8 / 4.2
CVE-2022-21980	Elevation of Privilege	Critical	CVSS:3.1 8.0 / 7.0
CVE-2022-24477	Elevation of Privilege	Critical	CVSS:3.1 8.0 / 7.0
CVE-2022-24516	Elevation of Privilege	Critical	CVSS:3.1 8.0 / 7.0
CVE-2022-30134	Elevation of Privilege	Important	CVSS:3.1 6.5 / 5.7 (was CVSS:3.1 7.6 / 6.6)

The following Security Updates address these vulnerability for the Exchange builds mentioned:

Exchange	Download	Build	KB	Supersedes
Exchange 2019 CU12	Download	15.2.1118.15	KB5019077	KB5015322
Exchange 2019 CU11	Download	15.2.986.30	KB5019077	KB5015322
Exchange 2016 CU23	Download	15.1.2507.13	KB5019077	KB5015322
Exchange 2016 CU22	Download	15.1.2375.32	KB5019077	KB5015322
Exchange 2013 CU23	Download	15.0.1497.42	KB5019076	KB5015321

Be advised that these security updates are Cumulative Update level specific. You cannot apply the update for Exchange 2019 CU12 to Exchange 2019 CU11. Also, the security update download has the same name for different Cumulative Updates, and I would suggest tagging the file name with the CU level, e.g. Exchange2019-CU12-KBXXXXXX-x64-en.msp.

Security Updates Exchange 2013-2019 (Aug2022)

Posted on August 9, 2022 by Michel de Rooij

The Exchange product group released Augustus updates for Exchange Server 2013, 2016 and 2019.

Note that per the previous May cycle, Security Updates will be packaged in an executable wrapper. This should trigger the running elevated prompt, thus preventing any potential issues when admins simply double-click the .MSP file. More about the new package format, options for logging and command-line switches are mentioned in an article dedicated to the change of distribution method here.

Windows Extended Protection
Special attention in this cycle for Windows Extended Protection, which needs to be enabled to address certain vulnerabilities. WEP is ONLY supported for specific versions of Exchange server – see the documentation for details regarding requirements and known issues. TLDR; – list might change over time, consult the pages linked earlier:

Requirements
- Supported on Exchange 2013 CU23, Exchange 2016 CU22 and Exchange Server 2019 CU11 or later, with the August 2022 Security Updates installed.
- Cannot be enabled on Exchange Server 2013 servers hosting Public Folders in co-existence with Exchange 2016/2019.
- Cannot be enabled on Exchange 2016 CU22 or Exchange 2019 CU11 or older hosting a Public Folder Hierarchy.
- Does not work with hybrid servers using Modern Hybrid configuration.
- SSL Offloading scenarios are currently not supported.
- Consistent TLS configuration is required across all Exchange servers.
Known Issues
- Retention Policies using action Move to Archive stops working.
- In Exchange 2013, the MAPI over HTTP probe OutlookMapiHttpCtpProbe might show FAILED.

To perform prerequisite checks and implement WEP, a supporting script ExchangeExtendedProtectionManagement.ps1 has been published. Since enabling WEP impacts how clients and Exchange server communicates, it is highly recommended to test this first on your specific configuration, especially with 3rd party products, before enabling it in production.

Security Updates
So, on with the security updates. The vulnerabilities addressed in the Security Updates for August are:

Vulnerability	Category	Severity	Rating
CVE-2022-21979	Information Disclosure	Important	CVSS:3.1 4.8 / 4.2
CVE-2022-21980	Elevation of Privilege	Critical	CVSS:3.1 8.0 / 7.0
CVE-2022-24477	Elevation of Privilege	Critical	CVSS:3.1 8.0 / 7.0
CVE-2022-24516	Elevation of Privilege	Critical	CVSS:3.1 8.0 / 7.0
CVE-2022-30134	Elevation of Privilege	Important	CVSS:3.1 7.6 / 6.6
CVE-2022-34692	Information Disclosure	Important	CVSS:3.1 5.3 / 4.6

The following Security Updates address this vulnerability:

Exchange	Download	Build	KB	Supersedes
Exchange 2019 CU12	Download	15.2.1118.12	KB5015322	KB5014261
Exchange 2019 CU11	Download	15.2.986.29	KB5015322	KB5014261
Exchange 2016 CU23	Download	15.1.2507.12	KB5015322	KB5014261
Exchange 2016 CU22	Download	15.1.2375.31	KB5015322	KB5014261
Exchange 2013 CU23	Download	15.0.1497.40	KB5015321	KB5014260

These Security Updates also fix the following issues:

KB5017261 Start-DatabaseAvailabilityGroup fails with BlockedDeserializeTypeException
KB5017430 E-Discovery search fails in Exchange Online

Exchange Announcements

Posted on June 4, 2022 by Michel de Rooij

Few days ago, the Exchange Product made several announcements related to Exchange Server and its future. The overall message throughout these announcements can be interpreted as that Microsoft is publicly declaring to be committed to developing and supporting the Exchange Server product. This is especially of interest to those customers running it as part of their on-premises infrastructure. It is also assuring those that believe the road ahead was a dead end, eventually forcing them to move to Exchange Online, or look for alternatives.

The announcements made were in the area of:

Lifecycle policies remain intact for current versions of Exchange Server.
The next version of Exchange Server, also known as Exchange vNext, will move to a continuous support model, but comes with requirements.
Upgrade path for Exchange vNext.
Modern Authentication support for non-hybrid Exchange 2019 deployments.
Exchange 2019 support for TLS 1.3.
Possibility to receive pre-release builds of Exchange server through Microsoft’s TAP program.
Exchange Admin Center will receive overview section for Exchange servers update status in Exchange hybrid deployments.
HCW will allow admins to skip configuration steps.
Script to remove obsolete mitigations from EEMS.
Microsoft Exchange ~~Conference~~ Community Virtual Airlift (MEC) for September 13-14! (register)
Feedback forums for Exchange Online and Exchange Server.

More details on these announcements can be found in the full article on the announcements, and can be found here at the ENow Solutions blog.

Exchange Updates (and more) – H1 2022

Posted on April 20, 2022 by Michel de Rooij

20220423: Added TLS 1.3 note.

The Exchange Team released the ~~quarterly~~ half-yearly Cumulative Updates for Exchange Server 2019 and Exchange 2016. You read that right, half-yearly updates are replacing the cadence of quarterly update servicing model for Exchange Server. Effectively, this will be Exchange 2019 only, as Exchange 2016 will be out of mainstream support in H2 of 2022, and will therefor only receive Security Updates after this round. Note that this change also alters the effective ‘current’ state (n-1 or later) of your Exchange Server environment from half year to one year.

And that’s not the only good news that comes with these sets of updates. In short:

If you run Exchange 2019 in Hybrid only for the purpose of managing recipients, you can now use Exchange 2019 CU12’s Exchange Management Tools to accomplish this; no more need to have an Exchange server running just for this. More details here.
Exchange 2019 CU12 will reintroduce the Hybrid Key option. Its Hybrid Configuration Wizard supports this licensing method.
Exchange 2019 CU12 support managing the Hybrid Agent with MFA-enabled accounts.
Exchange 2019 CU12 adds support for Windows Server 2022, both for its underlying operating system, as well as deployment in environments running Windows Server 2022 Domain Controllers.
Note that while Windows Server 2022 supports TLS 1.3, Exchange 2019 CU12 on WS2022 does not yet support it. Adding support is scheduled for somewhere next year.
The supportability matrix has been updated for the supported Windows Server 2022 scenarios.
Exchange Server is now also part of Microsoft’s Bounty Program, which is an indication of continued focus for customers still running Exchange Servers on-premises.

Links to the updates as well as a description of changes and fixes are described below. The column Schema and AD indicate if the CU contains Schema (/PrepareSchema) and Active Directory (PrepareAD) changes compared to the previous CU. Refer to the Exchange Schema page for schema and related versioning information.

Version	Build	KB	Download	UMLP	Schema	AD
Exchange 2019 CU12	15.2.1118.7	KB5011156	Download		N	Y
Exchange 2016 CU23	15.1.2507.6	KB5011155	Download	UMLP	N	Y

Apart from DST changes and the fixes mentioned below, these Cumulative Updates also contain a change which will not allow using UNC paths with several cmdlets. More information about this change and cmdlets affected can be found here: KB5014278.

Exchange 2019 CU12 fixes:

5012757 “Migration user… can’t be found” error when using Start-MigrationUser after batch migration fails
5012758 Start-MailboxAssistant is not available in Exchange Server 2019
5012760 You can’t access OWA or ECP after installing the July 2021 security update
5012761 External attendees see “Send the Response Now” although no response was requested in Exchange Server
5012762 PST creation is unexpectedly triggered again during multiple mailbox export
5012765 Email stuck in queue starting from “2022/1/1 00:01:00 UTC+0” on all Exchange on-premises servers
5012766 Transport Services fail repeatedly because of * Accepted Domain
5012768 Start-MigrationUser and Stop-MigrationUser are unavailable for on-premises Exchange Server 2019 and 2016
5012769 Invalid New Auth Certificate for servers that are not on UTC time zone
5012770 No response from public folder for users migrating to Microsoft Exchange 2019
5012772 Items are skipped at the start of a new search page request
5012773 OWAMailboxPolicy is bypassed and high resolution profile images can be uploaded
5012774 Can’t change default path for Trace log data in Exchange Server 2019 and 2016
5012775 No additional global catalog column in the address book service logs
5012776 Exchange Server 2019 help link in OWA redirects users to online help for Exchange Server 2016
5012777 Can’t find forwarded messages that contain attachments in Exchange Server 2019
5012778 Exchange Server stops responding when processing PDF files with set transport rule
5012779 Invalid new auth certificate for servers that are not on UTC time zone
5012780 Disable-Mailbox does not remove LegacyExchangeDN attribute from on-premises Exchange 2019
5012781 Exchange Server 2019 and 2016 DLP doesn’t detect Chinese resident ID card numbers
5012782 MS ExchangeDiagnostic Service causes errors during service startup and initialization in Microsoft Exchange 2019
5012783 Can’t restore data of a mailbox when LegacyDN is empty in the database
5012784 Exchange 2016 CU21 and Exchange 2019 CU10 cannot save “Custom Attributes” changes in EAC
5012785 Read Only Domain Controllers (RODCs) in other domains do not get desired permissions
5012786 Forwarded meeting appointments are blocked or considered spam
5012787 Download domains created per CVE-2021-1730 don’t support ADFS authentication in OWA
5012789 Can’t use Copy Search Results after eDiscovery & Hold search
5012790 OWA doesn’t remove the “loading” image when a message is opened in Chrome and Edge browsers
5012791 MailboxAuditLog doesn’t work in localized (non-English) environments

Exchange 2016 CU23 fixes:

5012757 “Migration user… can’t be found” error when using Start-MigrationUser after batch migration fails
5012760 You can’t access OWA or ECP after installing the July 2021 security update
5012761 External attendees see “Send the Response Now” although no response was requested in Exchange Server
5012765 Email stuck in queue starting from “2022/1/1 00:01:00 UTC+0” on all Exchange on-premises servers
5012768 Start-MigrationUser and Stop-MigrationUser are unavailable for on-premises Exchange Server 2019 and 2016
5012769 Invalid New Auth Certificate for servers that are not on UTC time zone
5012774 Can’t change default path for Trace log data in Exchange Server 2019 and 2016
5012779 Invalid new auth certificate for servers that are not on UTC time zone
5012780 Disable-Mailbox does not remove LegacyExchangeDN attribute from on-premises Exchange 2019
5012781 Exchange Server 2019 and 2016 DLP doesn’t detect Chinese resident ID card numbers
5012782 MS ExchangeDiagnostic Service causes errors during service startup and initialization in Microsoft Exchange 2019
5012783 Can’t restore data of a mailbox when LegacyDN is empty in the database
5012784 Exchange 2016 CU21 and Exchange 2019 CU10 cannot save “Custom Attributes” changes in EAC
5012786 Forwarded meeting appointments are blocked or considered spam
5012787 Download domains created per CVE-2021-1730 don’t support ADFS authentication in OWA
5012789 Can’t use Copy Search Results after eDiscovery & Hold search
5012791 MailboxAuditLog doesn’t work in localized (non-English) environments
5012829 Group metrics generation fails in multidomain environment

Notes:

If these Cumulative Updates contain schema changes compared to the Cumulative Update you currently have deployed, you need to run Setup with /PrepareSchema. If they contain Active Directory changes, you need to run /PrepareAD. Alternatively, permissions permitting, you can let Setup perform this step. Consult the Exchange schema versions page for schema and related versioning information.
When upgrading from an n-2 or earlier version of Exchange, or an early version of the .NET Framework, consult Upgrade Paths for CU’s & .NET.
Don’t forget to put the Exchange server in maintenance mode prior to updating. Regardless, setup will put the server in server-wide offline mode post-analysis, before making actual changes.
When using Exchange hybrid deployments or Exchange Online Archiving (EOA), support requires you to trail at most one version (n-1).
If you want to speed up the update process for systems without internet access, you can follow the procedure described here to disable publisher’s certificate revocation checking.
Cumulative Updates can be installed directly; no need to install RTM prior to installing Cumulative Updates.
Once upgraded, you can’t uninstall a Cumulative Update nor any of the installed Exchange server roles.
The recommended upgrade order is internet-facing, non-internet-facing servers first, followed by Edge Transports.

Caution:

As for any update, I recommend to thoroughly test updates in a test environment prior to implementing them in production. When you lack such facilities, hold out a few days and monitor the comments on the original publication or forums for any issues.