Security Updates for Spoofing Vulnerability

Ex2013 LogoUpdated April 12th: Notice on KB4487563

Today, as part of patch Tuesday, supported Exchange versions received security updates to remediate the following issues:

Security updates are available for the following product levels, and fix the vulnerability mentioned:

Build KB Download CVE-2019-0817 CVE-2019-0858
Exchange 2019 CU1 15.2.330.7 KB4487563 Download Yes Yes
Exchange 2019 15.2.221.16 KB4487563 Download Yes Yes
Exchange 2016 CU12 15.1.1713.6 KB4487563 Download Yes Yes
Exchange 2016 CU11 15.1.1591.16 KB487563 Download Yes Yes
Exchange 2013 CU22 15.0.1473.4 KB487563 Download Yes Yes
Exchange 2010 SP3 RU27 14.3.452.0 KB4491413 Download Yes No

Notes:

  • CVS-2019-0858 does not apply to Exchange 2010.
  • Exchange 2010 is currently in Extended Support. Extended support for Exchange 2010 ends January 14, 2020.
  • Don’t forget to put the Exchange server in maintenance mode prior to updating.
  • 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.
  • The order of installation shouldn’t matter with the “every server is an island” concept, yet recommended is to upgrade internet-facing first, followed by non-internet-facing servers, and finally Edge Transports.

Notice on KB4487563:
Apart from the known issues mentioned in KB4487563, there are reports the fix terminates while stopping services, and the following error is being logged:
[Error] System.Management.Automation.CommandNotFoundException: The term ‘Stop-SetupService’ is not recognized as the name of a cmdlet, function, script file, or operable program.

This Stop-SetupService isn’t a regular cmdlet, and I assume is an alias created by the update. However, there are reports this operation fails. In those circumstances, next to retrying installation of the update, a workaround might be opening up a PowerShell session and adding the alias yourself using New-Alias Stop-SetupService Stop-Service, followed by running the update. The alias isn’t persistent, so will be gone after you close your session.

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.

Exchange Updates – February 2019

Update: Added note that Exchange 2010 SP3 RU26 adds support for Windows Server 2012 R2.

Today, the Exchange Team released the overdue quarterly Cumulative Updates for Exchange Server 2013, Exchange 2016 and Exchange 2019, as well as a Rollup for Exchange Server 2010.

The KB articles that describe the fixes in each release and product downloads are available as follows:

Version Build KB Download UMLP Schema
Exchange 2019 CU1 15.2.330.5 KB4471391 VLSC N
Exchange 2016 CU12 15.1.1713.5 KB4471392 Download UMLP N
Exchange 2013 CU22 15.0.1473.3 KB4345836 Download UMLP N
Exchange 2010 SP3 RU26 14.3.442.0 KB4487052 Download N

This update contain the following important changes and notes:

  • Due to issue CVE-2018-8581, the EWS architecture was changed, in particular push notifications. Details on the change are described in KB4490060; while the change has been tested against EWS clients such as Outlook for Mac and Skype for Business, organizations may need to test any applications leveraging EWS to estimate potential impact of installing these Cumulative Updates or Rollup. In addition, organizations are advised to password reset Exchange computer accounts.
  • These Exchange builds introduces a change in the shared permissions model (this does not apply to Split Permissions Model). Result is that Exchange no longer requires fargoing permissions in Active Directory (e.g. WriteDACL on root of domain). To makes these changes become effective:
    • For Exchange 2013-2019 Cumulative Updates, run setup using /PrepareAD. In multi-forest environments, this needs to be done in every domain of the forest.
    • For Exchange 2010, go through the instructions mentioned in KB4490059.
  • Organizations considering moving to the Split Permissions because of CVE-2018-8581 should know Microsoft fully supports both models. Switching can have serious consequences and therefor should be fully evaluated.
  • This build of Exchange 2019 introduces cmdlets to block usage of legacy authentication protocols for users through policies, e.g. Basic Authentication.
  • Prior to deploying Exchange 2016 CU12 or Exchange 2013 CU22 on Edge Transport servers, install Visual C++ 2012 Runtime.
  • These Cumulative Updates will remove the DisableLoopbackCheck key when present; removing this key was a mitigation for CVE-2018-8581.
  • Exchange 2010 SP3 RU26 adds support for Windows Server 2012 R2, to accommodate for the Hybrid Agent.

Exchange 2019 CU1 fixes:

  • 4487596 Emails are blocked in moderator mailbox Outbox folder when you send large volumes of emails in Exchange Server 2019
  • 4487591 The recipient scope setting doesn’t work for sibling domains when including OUs in the scope in Exchange Server 2019
  • 4487602 Outlook for Mac users can still expand a distribution group when hideDLMembership is set to true in Exchange Server 2019
  • 4488076 Outlook on the Web can’t be loaded when users use an invalid Windows language in operating system in Exchange Server 2019
  • 4488079 Exchange Server 2016 allows adding Exchange Server 2019 mailbox server into a same DAG and vice versa
  • 4488263 X-MS-Exchange-Organization-BCC header isn’t encoded correctly in Exchange Server 2019
  • 4488080 New-MigrationBatch doesn’t honor RBAC management scope in Exchange Server 2019
  • 4488262 Delivery Reports exception when tracking a meeting request that’s sent with a room resource in Exchange Server 2019
  • 4488268 Disable the irrelevant Query logs that’re created in Exchange Server 2019
  • 4488267 Test-OAuthConnectivity always fails when Exchange Server uses proxy to connect to Internet in Exchange Server 2019
  • 4488266 Client application doesn’t honor EwsAllowList in Exchange Server 2019
  • 4488265 “There are problems with the signature” error occurs for digital signature message if attachment filtering is enabled in Exchange Server 2019
  • 4488398 “The Microsoft Exchange Replication service may not be running on server” error when you add a mailbox database copy in Exchange Server 2019
  • 4488264 Mailbox that has a bad move request can’t be cleaned up from destination mailbox database in Exchange Server 2019
  • 4488261 Event ID 1002 when the store worker process crashes in Exchange Server 2019
  • 4488260 New-MailboxExportRequest and New-MailboxImportRequest don’t honor RBAC management scope in Exchange Server 2019
  • 4488259 MailTip shows wrong number of users for a distribution group if the users are in different domains in Exchange Server 2019
  • 4488258 OAuth authentication is removed when saving MAPI virtual directory settings in EAC in Exchange Server 2019
  • 4490060 Exchange Web Services Push Notifications can be used to gain unauthorized access
  • 4490059 Reducing permissions required to run Exchange Server using Shared Permissions Model

Exchange 2016 CU12 fixes:

  • 4487596 Emails are blocked in moderator mailbox Outbox folder when you send large volumes of emails in Exchange Server 2016
  • 4456241 You receive a meeting request that has a “not supported calendar message.ics” attachment in Exchange Server 2016
  • 4456239 New-MailboxRepairRequest doesn’t honor RBAC RecipientWriteScope restrictions in Exchange Server 2016
  • 4487591 The recipient scope setting doesn’t work for sibling domains when including OUs in the scope in Exchange Server 2016
  • 4468363 MRM does not work for mailboxes that have an online archive mailbox in Exchange Server
  • 4487603 “The action cannot be completed” error when you select many recipients in the Address Book of Outlook in Exchange Server 2016
  • 4487602 Outlook for Mac users can still expand a distribution group when hideDLMembership is set to true in Exchange Server 2016
  • 4488076 Outlook on the Web can’t be loaded when users use an invalid Windows language in operating system in Exchange Server 2016
  • 4488079 Exchange Server 2016 allows adding Exchange Server 2019 mailbox server into a same DAG and vice versa
  • 4488077 Can’t configure voice mail options when user is in different domain in Exchange Server 2016
  • 4488263 X-MS-Exchange-Organization-BCC header isn’t encoded correctly in Exchange Server 2016
  • 4488080 New-MigrationBatch doesn’t honor RBAC management scope in Exchange Server 2016
  • 4488262 Delivery Reports exception when tracking a meeting request that’s sent with a room resource in Exchange Server 2016
  • 4488268 Disable the irrelevant Query logs that’re created in Exchange Server 2016
  • 4488267 Test-OAuthConnectivity always fails when Exchange Server uses proxy to connect to Internet in Exchange Server 2016
  • 4488266 Client application doesn’t honor EwsAllowList in Exchange Server 2016
  • 4488265 “There are problems with the signature” error occurs for digital signature message if attachment filtering is enabled in Exchange Server 2016
  • 4488264 Mailbox that has a bad move request can’t be cleaned up from destination mailbox database in Exchange Server 2016
  • 4488261 Event ID 1002 when the store worker process crashes in Exchange Server 2016
  • 4488260 New-MailboxExportRequest and New-MailboxImportRequest don’t honor RBAC management scope in Exchange Server 2016
  • 4488259 MailTip shows wrong number of users for a distribution group if the users are in different domains in Exchange Server 2016
  • 4488258 OAuth authentication is removed when saving MAPI virtual directory settings in EAC in Exchange Server 2016
  • 4490060 Exchange Web Services Push Notifications can be used to gain unauthorized access
  • 4490059 Reducing permissions required to run Exchange Server using Shared Permissions Model

Exchange 2013 CU22 fixes:

  • 4487603 “The action cannot be completed” error when you select many recipients in the Address Book of Outlook in Exchange Server 2013
  • 4490060 Exchange Web Services Push Notifications can be used to gain unauthorized access
  • 4490059 Reducing permissions required to run Exchange Server using Shared Permissions Model

Exchange 2010 SP3 RU26 fixes:

  • 4490060 Exchange Web Services Push Notifications can be used to gain unauthorized access

Notes:

  • These Cumulative Updates do not contain schema changes compared to their previous Cumulative Update. However, due to changes in the permissions architecture, you need to run setup /PrepareAD to implement these changes as well as apply any RBAC changes, before deploying or updating Exchange servers.
  • 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), you are required to delay installing 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 installed, you can’t uninstall a Cumulative Update nor any of the installed Exchange server roles.
  • The order of installation shouldn’t matter with the “every server is an island” concept, yet recommended is to upgrade 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.

Security Updates Exchange 2013, 2016 & 2019

Ex2013 LogoUpdate 14jan: Added Exchange 2010 SP3 RU25

A quick heads-up as during my vacation Microsoft released security updates for supported releases of Exchange Server 2013, 2016 as well as Exchange Server 2019. In addition, a new Rollup was released for Exchange 2010 as well, containing one of the security updates.

The security updates patch issues as reported in the following Microsoft Common Vulnerabilities and Exposures:

  • CVE-2019-0586: Microsoft Exchange Memory Corruption Vulnerability
  • CVE-2019-0588: Microsoft Exchange Information Disclosure Vulnerability

You can download the security updates here:

Notes:

  • Exchange 2010 SP3 RU25 addresses CVE-2019-0588 only.
  • KB4471389 supersedes KB4468741 and KB4459266; KB4468742 supersedes KB4458321.

Be advised that the Security Updates for Exchange 2013 and 2016 are Cumulative Update level specific. Unfortunately, the security update carries the same name for different CU’s, and you cannot apply the update for Exchange 2016 CU10 to Exchange 2016 CU11. I would suggest tagging the Cumulative Update in the file name when you archive it, e.g. Exchange2016-KB4471389-x64-en-CU10.msp.

As with any patch or update, I’d recommend to thoroughly test this in a test and acceptance environment first, prior to implementing it in production.

Security Updates for Exchange 2016

Ex2013 LogoA quick heads-up as Microsoft released security update for supported releases of Exchange Server 2016.

The security updates patch issues as reported in the following Microsoft Common Vulnerabilities and Exposures:

  • CVE-2018-8604: Microsoft Exchange Server Tampering Vulnerability
    A tampering vulnerability exists when Microsoft Exchange Server fails to properly handle profile data. An attacker who successfully exploited this vulnerability could modify a targeted user’s profile data.

You can download the security updates here:

Notes:

  • KB4468741 for Exchange Server 2016 CU10 supersedes KB4459266.

As with any patch or update, I’d recommend to thoroughly test this in a test and acceptance environment first, prior to implementing it in production.

 

Security Updates for Exchange 2016, 2013 and 2010

Ex2013 LogoA quick heads-up as during my vacation Microsoft released security updates for supported releases of Exchange Server 2016 and 2013 as well as Exchange Server 2010.

The security updates patch issues as reported in the following Microsoft Common Vulnerabilities and Exposures:

  • CVE-2018-8302 Microsoft Exchange Memory Corruption Vulnerability
  • CVE-2018-8374 Microsoft Exchange Server Tampering Vulnerability (Exchange 2016 only)

You can download the security updates here:

Notes:

  • Be advised that Exchange 2010 SP3 Rollup 23, like recent Cumulative Updates of Exchange 2016 and 2013, requires Visual C++ Redistributable Packages for Visual Studio 2013 (download).
  • KB4340731 supersedes the previous security update KB4092041 for Exchange 2016 and Exchange 2013.

Be advised that for Exchange 2013 and 2016, Security Updates are Cumulative Update level specific. While the downloaded security updates may carry the same name, the files are different and you cannot apply the downloaded security update file for Exchange 2016 CU8 to Exchange 2016 CU9. I suggest adding some form of identification of the Cumulative Update to the file name when you archive it, e.g. Exchange2016-KB4340731-x64-en-CU10.msp.

As with any patch or update, I’d recommend to thoroughly test this in a test and acceptance environment first, prior to implementing it in production.

Issues with July Updates of Windows

bandaidLast Update July 19th: Corrected Update information.

About a week ago, Microsoft released the July Updates for Windows systems. Unfortunately, something must have gone wrong in quality control, because people were reporting all sorts of issues, mostly related to IIS and Exchange servers.

The issue is created at the operating system level, probably due to changes in networking as mentioned in the July update notes. Therefor, symptoms can be experienced on systems running Exchange Server 2016 or even back to Exchange Server 2007.

Some of the symptoms are:

  • The World Wide Web Publishing Service – W3SVC – won’t come up, remains in a “stopping” state, but cannot fully stop or it cannot be restarted.
  • Exchange Transport and SMTP services becomes unresponsive or stops, causing mail flow issues (Source).

The issues were serious enough to have the Exchange PG publish a notice.

Meanwhile, Microsoft has released a superseding update for Windows Server 2016, and updates for older operating systems. However, looking at the information provided with updates for older operating systems, there are fixes for the original security updates, and (previews of) Monthly Rollups for the July updates. Replacements and updates may manifest themselves in Windows Update only after installing the original – faulty – update, meaning you might have to go through more than one Windows Update cycle (and possibly reboot) for the updates to become visible and installable. This applies to the Monthly Rollups as well.

The table below contains information on the original rollups and updates, the update you need to apply, and the type of update.

Operating System Original Update Update Type Comments
Windows Server 2016 KB4338814 KB4345418 Monthly Rollup Replacement
Windows Server 2012 R2 KB4338815 KB4338831 Monthly Rollup Replacement
KB4338824 KB4345424 Security Update Update for v1
Windows Server 2012 KB4338830 KB4338816 Monthly Rollup Replacement
KB4338820 KB4345425 Security Update Update for v1
Windows Server 2008 R2 KB4338823 KB4345459 Security Update Update for v1
KB4338818 KB4338821 Monthly Rollup Replacement
Windows Server 2008 KB4295656 KB4345397 Security Update Update for v1

Finally, apart from adopting a less aggressive updating strategy, this again shows unfortunately that having a separate production environment next to your test environment is no frivolous luxury.

Security Updates for Exchange 2016, 2013 and 2010

Ex2013 LogoA quick heads-up for those that missed it that earlier this month, as Microsoft released security updates for supported releases of Exchange Server 2016 and 2013 as well as Exchange Server 2010.

The security updates patch issues as reported in the following Microsoft Common Vulnerabilities and Exposures:

  • CVE-2018-8151 – Microsoft Exchange Memory Corruption Vulnerability
  • CVE-2018-8154 – Microsoft Exchange Memory Corruption Vulnerability
  • CVE-2018-8159 – Microsoft Exchange Elevation of Privilege Vulnerability
  • CVE-2018-8153 – Microsoft Exchange Spoofing Vulnerability
  • CVE-2018-8152 – Microsoft Exchange Server Elevation of Privilege Vulnerability

You can download the security updates here:

You may notice that Exchange 2013 Service Pack 1 is still in there, but this is because Cumulative Updates and Service Packs are on a different servicing model. Every Cumulative Update is supported for three months after the release of the next Cumulative Update; Exchange 2013 SP1 entered extended support early April, and will only receive critical updates such as this one.

Be advised that for Exchange 2013 and 2016, Security Updates are Cumulative Update level specific. While the downloaded security updates may carry the same name, the files are different and you cannot apply the downloaded security update file for Exchange 2016 CU8 to Exchange 2016 CU9. I suggest adding some form of identification of the Cumulative Update to the file name when you save it, e.g. Exchange2016-KB4092041-x64-en-CU9.msp.

As with any patch or update, I’d recommend to thoroughly test this in a test and acceptance environment first, prior to implementing it in production.

 

Security Updates for Exchange 2013 & 2016

Despite the quarterly wave of Cumulative Updates being imminent, CVE-2017-11932 and ADV170023 warranted a quick release of Security Update KB4045655 for current versions of Exchange 2013 and Exchange 2016.

This security update fixes a vulnerability in OWA, which could allow elevation of privilege or spoofing if an attacker sends an email that has a specially crafted attachment to a vulnerable Exchange server.

You can download the security updates here:

Be advised the update may leave your Exchange services in a disabled state, despite installing correctly. In those cases, reconfigure those services to Automatic and start them manually.

Also note that this security update overrides an earlier update, KB4036108, which might cause Calendar Sharing issues when split DNS is used.

Security updates are Cumulative Update level specific. Be advised that updates may carry the same name, e.g. the update for CU7 and the one for CU6 are both Exchange2016-KB4045655-x64-en.msp. I suggest adding some form of Cumulative Update identification to the file name when archiving it, e.g. Exchange2016-KB4045655-x64-en-CU7.msp.

As with any patch or update, I’d recommend to thoroughly test this in a test and acceptance environment first, prior to implementing it in production.

 

Exchange 2010-2016 Security Fixes

Ex2013 LogoMicrosoft released security updates to fix a remote code execution vulnerability in Exchange Server. The related knowledge base article is KB4018588.

More information is contained in the following Common Vulnerabilities and Exposures articles:

  • CVE-2017-8521 – Scripting Engine Memory Corruption Vulnerability
  • CVE-2017-8559 – Microsoft Exchange Cross-Site Scripting Vulnerability
  • CVE-2017-8560 – Microsoft Exchange Cross-Site Scripting Vulnerability

Depending on the lifecycle status of the product, fixes are made available either through a Rollup or as a security fix for the following product levels:

As you might notice, the security fix is made available for the N-1 builds of Exchange 2013 and Exchange 2016. This could imply the issue was addressed in the latest builds of those products. I hope to receive official confirmation on this soon.

The issue is deemed Important, which means organizations are advised to apply these updates at the earliest opportunity. However, as with any update, it is recommended to thoroughly test updates and fixes prior to deploying them in a production environment.

MS17-015: Security Fix for Exchange 2013 SP1+CU14 & 2016 CU3

Ex2013 LogoMicrosoft published security fixes for the issue described in bulletin MS17-105. Fixes have been released for the following product levels:

You are reading it correctly: the later Cumulative Updates are not affected. Earlier builds will not receive a security fix, as support is provided up to N-2 generation builds. Reason for Exchange 2013 SP1 being in there is that Service Packs are on a different support scheme.

Note that this Rollup or security fix replaces MS16-108 (kb3184736) – you can install MS13-105 over installations containing this security fix (no need to uninstall it first).