August 5, 2015 By Shane Schick 2 min read

The Windows 10 update marks a major turning point for Microsoft customers who want to move to a cloud-based version of the classic operating system, but researchers say cybercriminals are acting quickly to dupe early adopters into installing ransomware as part of their upgrade.

Unlike previous versions of the OS that required a local installation, Microsoft is offering the Windows 10 update through a software-as-a-service (SaaS) model. However, Cisco revealed that cybercriminals are creating versions of the company’s email messages that, if clicked on, will inject the CTB Locker malware onto devices. A PC or tablet with CTB Locker installed will essentially be frozen unless the victim makes a cash payment within a four-day period. As CSO Online pointed out, the cybercriminals have replicated the Microsoft marketing materials very well, so be careful about what you open in your inbox regarding Windows 10.

The ransomware threat runs directly counter to Microsoft’s efforts to bolster its reputation for security with its Windows 10 update. For example, Trend Micro recently detailed major improvements in Edge, which will replace the Internet Explorer browser as part of the OS refresh. While IE had often been a target for attackers, Edge has done away with toolbars and Browser Helper Objects, which have proven vulnerable in the past. At the same time, Edge will include features such as an Enhanced Protected Mode sandbox, a way to deal with memory corruption and a tool for sweeping out what are known as use-after-free (UAF) exploits.

According to some experts, though, Microsoft may have overlooked a few other default features that could rile security professionals and put consumers at risk without being aware of it. The Hacker News reported that the Windows 10 update contains a mechanism called Windows Update Delivery Optimization (WUDO). While the concept of WUDO is well-intended — allowing those with a poor or limited Internet connection to get apps or updates quickly — the feature can also use up significant bandwidth. Throw in the way cybercriminals have traditionally used torrents to distribute malware, and it may be best in some cases to disable WUDO.

Of course, the Windows 10 update is the kind of thing that will trigger many computer users to make a significant change to their machines, so it’s not surprising that cybercriminals would want to find a way to get in on the action. And while Microsoft has suggested that in some ways this would be its last OS, don’t expect these to be the last security warnings you hear about it.

More from

SoaPy: Stealthy enumeration of Active Directory environments through ADWS

10 min read - Introduction Over time, both targeted and large-scale enumeration of Active Directory (AD) environments have become increasingly detected due to modern defensive solutions. During our internship at X-Force Red this past summer, we noticed FalconForce’s SOAPHound was becoming popular for enumerating Active Directory environments. This tool brought a new perspective to Active Directory enumeration by performing collection via Active Directory Web Services (ADWS) instead of directly through Lightweight Directory Access Protocol (LDAP) as other AD enumeration tools had in the past.…

Smoltalk: RCE in open source agents

26 min read - Big shoutout to Hugging Face and the smolagents team for their cooperation and quick turnaround for a fix! Introduction Recently, I have been working on a side project to automate some pentest reconnaissance with AI agents. Just after I started this project, Hugging Face announced the release of smolagents, a lightweight framework for building AI agents that implements the methodology described in the ReAct paper, emphasizing reasoning through iterative decision-making. Interestingly, smolagents enables agents to reason and act by generating…

4 ways to bring cybersecurity into your community

4 min read - It’s easy to focus on technology when talking about cybersecurity. However, the best prevention measures rely on the education of those who use technology. Organizations training their employees is the first step. But the industry needs to expand the concept of a culture of cybersecurity and take it from where it currently stands as an organizational responsibility to a global perspective.When every person who uses technology — for work, personal use and school — views cybersecurity as their responsibility, it…

Topic updates

Get email updates and stay ahead of the latest threats to the security landscape, thought leadership and research.
Subscribe today