Security researchers have discovered a new cybercriminal approach that takes advantage of Microsoft’s webmail server to gain access to corporate systems and potentially steal information.

Webmail Servers Are Vulnerable

Israel-based firm Cybereason outlined the details of its findings, which showed how Outlook Web Access (OWA), the webmail server associated with Microsoft’s popular email client, was the target of at least one incident involving an unnamed public service organization in the U.S. The attackers were able to exploit the fact that OWA works as a sort of middleman between the Internet and internal systems by uploading a DLL file that opened a backdoor when users authenticated into the system. Cybercriminals were then able to spread malware every time the server restarted. This could provide cybercriminals with access to passwords and other critical data, SecurityWeek reported.

As more employees work outside the office via mobile devices, many companies are increasingly looking at OWA, Gmail and similar programs as a way to enable remote access to email. However, the Microsoft webmail server is unique in the way it sits between the public-facing Internet and a business’s IT systems, SC Magazine explained.

Depending on the configuration and the number of endpoints across which scripts have been put into place, cybercriminals can gain domain credentials that give them disturbingly deep access over user identities. In this case, Cybereason suggested the organization it profiled had been compromised for months.

Cybercriminal Workarounds

Of course, the OWA webmail server isn’t the only such system prone to attack. Just a few months ago, The Register reported on how researchers discovered a man-in-the-middle vulnerability in a Samsung smart fridge, which could potentially steal Gmail logins. Given that few organizations will want to go back to the days when you could only access messages at your desk, however, IT departments will need to come up with ways to better protect corporate users.

Infosecurity Magazine offered a few helpful suggestions. First, organizations need to make sure all endpoints, including not only webmail servers but databases and Active Directory servers, are monitored regularly for anomalies. Second, CISOs and their teams could have a process in place to respond to any suspicious activity and verify whether, for example, a DLL file is legitimate or not. Finally, they should recognize that advanced persistent threats like this one will likely be outside the norm of what they’ve experienced in the past. As the Cybereason research proves, cybercriminals seem to be finding new ways into the network every day.

More from

Data Privacy: How the Growing Field of Regulations Impacts Businesses

The proposed rules over artificial intelligence (AI) in the European Union (EU) are a harbinger of things to come. Data privacy laws are becoming more complex and growing in number and relevance. So, businesses that seek to become — and stay — compliant must find a solution that can do more than just respond to current challenges. Take a look at upcoming trends when it comes to data privacy regulations and how to follow them. Today's AI Solutions On April…

Why Zero Trust Works When Everything Else Doesn’t

The zero trust security model is proving to be one of the most effective cybersecurity approaches ever conceived. Zero trust — also called zero trust architecture (ZTA), zero trust network architecture (ZTNA) and perimeter-less security — takes a "default deny" security posture. All people and devices must prove explicit permission to use each network resource each time they use that resource. Using microsegmentation and least privileged access principles, zero trust not only prevents breaches but also stymies lateral movement should a breach…

5 Golden Rules of Threat Hunting

When a breach is uncovered, the operational cadence includes threat detection, quarantine and termination. While all stages can occur within the first hour of discovery, in some cases, that's already too late.Security operations center (SOC) teams monitor and hunt new threats continuously. To ward off the most advanced threats, security teams proactively hunt for ones that evade the dashboards of their security solutions.However, advanced threat actors have learned to blend in with their target's environment, remaining unnoticed for prolonged periods. Based…

Third-Party App Stores Could Be a Red Flag for iOS Security

Even Apple can’t escape change forever. The famously restrictive company will allow third-party app stores for iOS devices, along with allowing users to “sideload” software directly. Spurring the move is the European Union’s (EU) Digital Markets Act (DMA), which looks to ensure open markets by reducing the ability of digital “gatekeepers” to restrict content on devices. While this is good news for app creators and end-users, there is a potential red flag: security. Here’s what the compliance-driven change means for…