Microsoft Exchange and Active Directory Blog
Support for Exchange Server 2013 ends on 11.04.2023, after this date there will be no more security updates for Exchange 2013. It is therefore high time to consider the migration from Exchange 2013 to Exchange 2019. The migration should not present any major hurdles and corresponds almost 1-to-1 to the migration from Exchange 2013 to ... Read more
Extended support for Exchange Server 2013 will end on April 11, 2023. As of April 11, there will no longer be any security updates for Exchange 2013 in addition to the lack of support. So there will be little time left to migrate to a newer Exchange Server version or to Microsoft 365. Anyone still using Exchange 2013 Server should ... Read more
Microsoft has released new security updates for Exchange Server 2013, 2016 and 2019 today. The security updates also include a new security feature, which currently still needs to be activated manually: Click here to download the security updates: The security updates fix the following security vulnerabilities classified as important: New security feature: Certificate Signing of PowerShell Serialization Payload To prevent ... Read more
I have just uploaded version 3.12 of the Exchange Reporter. The new version fixes 3 small bugs: The current version can be downloaded here: If you find any problems, please use the following form to report them. You can also use the form to send feature requests or other suggestions: I am currently working on the Exchange ... Read more
Attacks on outdated Exchange servers are currently underway again. Specifically, the ProxyNotShell vulnerability, which became known in October of this year, is being exploited again. The new attack method has been christened OWASSRF. The IIS rewrite rules published by Microsoft are bypassed in this new attack method. The only thing that helps at the moment is to install the available security updates from November: On the ... Read more
On Tuesday, Microsoft released new security updates for Exchange Server 2013, 2016 and 2019. The update closes the ProxyNotShell vulnerability (CVE-2022-41040 and CVE-2022-41082), which was known and actively exploited in September. Click here to download the security updates: Microsoft recommends installing the update as soon as possible. Click here for the article on the Exchange ... Read more
Two Outlook Autodiscover settings, which are active in the default setting, often cause problems when setting up Outlook accounts. In the default setting, Outlook always tries to retrieve Autodiscover settings from Microsoft 365, which often leads to problems with on-prem Exchange servers. Outlook also tries to retrieve the Autodiscover settings from the root domain ... Read more
I have just uploaded the new version 3.11 of the Exchange Reporter. The new version contains the module "ExchangeMitigations", which shows the status of the Exchange Emergency Mitigation Service and the applied rules. Here is an example report of the new module: Various bugs have also been fixed, the module "Healthchecker", which executes the Exchange Health Checker Script and displays in ... Read more
Microsoft has released new security updates for all supported Exchange Server versions today. Microsoft explicitly points out that the updates do not contain a fix for the zero-day vulnerabilities (ProxyNotShell). The following vulnerabilities are fixed by the security update, three of the vulnerabilities are considered critical: CVE-2022-21979 CVE-2022-21980 CVE-2022-24477 CVE-2022-24516 CVE-2022-30134 The updates can be downloaded here: Exchange Server ... Read more
The Exchange Mitigation EM1, which was published by Microsoft at the weekend, does not adequately seal the Exchange zero-day vulnerability ProxyNotShell (CVE-2022-41040) and can be easily bypassed. The problem is an "@" character in the Reg-Ex pattern, which makes the rule too precise. The Reg-Ex can thus be bypassed by making slight adjustments. This means that the rule is no longer ... Read more
