If you're one of those Exchange Server administrators who’d rather hit snooze on update alarms, you might want to rethink that strategy. Microsoft's recent advisory highlights that failing to update your Exchange Servers could land you in unexpected hot water, especially when it comes to the crucial Exchange Emergency Mitigation Service (EEMS). Here’s the scoop.
However, this tool only works effectively if your Exchange Server keeps pace with cumulative updates (CUs) and security updates (SUs). Microsoft’s latest warning lays it all out: "Significantly out of date" versions of Exchange may soon find their EEMS life support cut off. In simpler terms: if you’re slacking on updates, you’re skating on thin ice.
Microsoft assures that any Exchange Server updated with a CU or SU newer than March 2023 will be fine and will retain its ability to fetch mitigations via EEMS. However, Exchange versions still living in the pre-March 2023 era are classified as “significantly out of date” and at risk of losing the ability to download newer EEMS configurations. The message? Get updating yesterday!
Additionally, vulnerabilities in Exchange Servers are frequently exploited by cybercriminals to compromise email systems. These can include spear phishing attempts, data exfiltration, or even backdoors for espionage, such as those observed in recent cybersecurity trends. EEMS provides quick, automated safeguards, but its reliance on regular updates makes it imperative for administrators to maintain their systems.
Consider this analogy: running an outdated Exchange Server today is like using an old antivirus program and expecting it to catch the latest malware. At best, you’re vulnerable. At worst? Catastrophic system failure. The “significantly out-of-date” servers are labeled as such because they handle critical vulnerabilities poorly by design—they lack the patches essential to guarding against emerging threats.
Microsoft has even delayed the release of a new Exchange Server version beyond its original schedule (now pushed deep into 2025) just to focus on addressing longstanding security concerns. While Exchange Server 2019 enjoys the spotlight as its latest incarnation, it can only remain the “greatest” if its administrators actually keep it updated.
And let’s call out the obvious: if you’re still holding onto Exchange Server versions that are this far behind the times, it might be worth reevaluating your need for an on-premises server in the first place. With robust email solutions on Microsoft 365, the phrase “on-premises” may someday evoke the kind of nostalgia reserved for dial-up internet.
But for those forging ahead with Exchange Server, now’s the time to step up. Update it. Secure it. Protect it. Because if EEMS isn’t there to save you when things go south, you may find yourself relegated to a much more vulnerable position in an increasingly hostile digital landscape.
What about you, WindowsForum readers? Is your Exchange Server up-to-date, or are you heading straight for a non-functional EEMS experience? Drop your thoughts (and update war stories) in the comments!
Source: The Register https://www.theregister.com/2025/01/24/microsoft_has_a_warning_for/
The Exchange Emergency Mitigation Service: What Is It?
The Exchange Emergency Mitigation Service (EEMS), introduced in September 2021, acts like Exchange Server’s frontline medic. Its job? To quickly apply temporary mitigations in critical situations, where vulnerabilities in Exchange Server could expose organizations to cyberattacks. Essentially, it connects to the Office Configuration Service (OCS) to fetch the latest mitigation configurations available from Microsoft. Like a vigilant paramedic, it ensures that your server has a safety net in place while you plan a more permanent solution—namely, installing updates.However, this tool only works effectively if your Exchange Server keeps pace with cumulative updates (CUs) and security updates (SUs). Microsoft’s latest warning lays it all out: "Significantly out of date" versions of Exchange may soon find their EEMS life support cut off. In simpler terms: if you’re slacking on updates, you’re skating on thin ice.
Why the Concern Now?
The reason for Microsoft's urgency is due to the deprecation of an older certificate type used by OCS. This change means Exchange Servers running outdated versions might be unable to connect to the service for updated mitigations—essentially cutting them off from critical defenses.Microsoft assures that any Exchange Server updated with a CU or SU newer than March 2023 will be fine and will retain its ability to fetch mitigations via EEMS. However, Exchange versions still living in the pre-March 2023 era are classified as “significantly out of date” and at risk of losing the ability to download newer EEMS configurations. The message? Get updating yesterday!
The Update Timeline: A Refresher
Let’s put this into a brief timeline of which Exchange updates are considered essential markers in this context:- March 2023 Security Update: This update targeted critical vulnerabilities, such as fixing EEMS issues where it stopped responding after a TLS endpoint certificate update.
- CUs and SUs Post-March 2023: If you’re running Exchange Server 2019 or 2016 and have updated to cumulative or security patches rolled out since March 2023, you're in the green. Anything older? Not so much.
What Happens If EEMS Stops Working?
Think of EEMS as your car’s emergency braking system while driving near sharp turns. Without it, you’re relying purely on manual steering and brakes—which means you’ll have to react to every danger manually, in real time. Without EEMS functioning, Exchange administrators will find themselves scrambling to deploy manual mitigations against looming threats, elongating response times and increasing risk exposure.Additionally, vulnerabilities in Exchange Servers are frequently exploited by cybercriminals to compromise email systems. These can include spear phishing attempts, data exfiltration, or even backdoors for espionage, such as those observed in recent cybersecurity trends. EEMS provides quick, automated safeguards, but its reliance on regular updates makes it imperative for administrators to maintain their systems.
What Does Microsoft Define as "Significantly Out of Date"?
Let’s decode Microsoft’s not-so-subtle nudge. By "significantly out of date," Microsoft seems to be drawing a very stark line at March 2023. Cumulative updates and patches are released regularly, and being over two cycles behind sets off alarms for Microsoft for good reason.Consider this analogy: running an outdated Exchange Server today is like using an old antivirus program and expecting it to catch the latest malware. At best, you’re vulnerable. At worst? Catastrophic system failure. The “significantly out-of-date” servers are labeled as such because they handle critical vulnerabilities poorly by design—they lack the patches essential to guarding against emerging threats.
Why Exchange Server Desperately Needs Vigilant Maintenance
Exchange Server has a storied history, to put it gently, of security vulnerabilities. In the past few years, its reputation has repeatedly been gold dust for cybercriminals. Attackers have leveraged unpatched vulnerabilities in Exchange to execute ransomware operations, steal data, and exploit server infrastructures.Microsoft has even delayed the release of a new Exchange Server version beyond its original schedule (now pushed deep into 2025) just to focus on addressing longstanding security concerns. While Exchange Server 2019 enjoys the spotlight as its latest incarnation, it can only remain the “greatest” if its administrators actually keep it updated.
What Should You Do?
So, if you're an Exchange admin, how do you get ahead of this looming issue? Here’s a quick plan:- Check Your Current Version: Open Exchange Admin Center or use PowerShell to check which CU and SU your server is running.
- Update ASAP: If your version is older than March 2023, prioritize upgrading to a newer CU or SU immediately. Updates are available for Exchange Server 2019, 2016, and even older versions (though they carry their own limitations).
- Commit to Patch Discipline: Security patches, especially for Exchange Server, must become a routine part of administration.
Closing the Gap Between Risks and Readiness
While Microsoft’s notice might jolt some complacent users into action, it shouldn't have taken an alert like this to stress what’s become a painfully evident reality: regular server maintenance directly correlates to how safe and functional your business remains.And let’s call out the obvious: if you’re still holding onto Exchange Server versions that are this far behind the times, it might be worth reevaluating your need for an on-premises server in the first place. With robust email solutions on Microsoft 365, the phrase “on-premises” may someday evoke the kind of nostalgia reserved for dial-up internet.
But for those forging ahead with Exchange Server, now’s the time to step up. Update it. Secure it. Protect it. Because if EEMS isn’t there to save you when things go south, you may find yourself relegated to a much more vulnerable position in an increasingly hostile digital landscape.
What about you, WindowsForum readers? Is your Exchange Server up-to-date, or are you heading straight for a non-functional EEMS experience? Drop your thoughts (and update war stories) in the comments!
Source: The Register https://www.theregister.com/2025/01/24/microsoft_has_a_warning_for/
