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4/2/2020
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A Hacker's Perspective on Securing VPNs As You Go Remote

As organizations rush to equip and secure their newly remote workforce, it's important to keep things methodical and purposeful

Faced with the certainty of organizational and global impact, and trying to urgently be a good corporate citizen, of course your organization is sending staff home. And while HR and finance are struggling with how to manage PTO and benefits for scores of sick employees, IT is scrambling to get as many employees as possible productive from their brand new (and ill equipped) home offices.

Despite national strategic exercises regarding pandemics, and in spite of a culture obsessed with zombies and prepping, very few organizations are actually prepared. So when leadership says "Let them work remotely," what are IT and security to do? They let them work remotely of course. However, the rapid transition from in-house to pure remote has to be done well, or an already horrible situation might well be far worse.

Perhaps an idea that we've all recently learned applies to this new situation: While helping the world flatten the curve for a pandemic, we need to do the same thing with the other risks we're addressing at our organizations. The pressure to move fast is immense, but it's critical to make sure we don't increase the risk curve by rushing and overwhelming the business-- and create a dream scenario for an adversary in the process. We need to make sure that our organizational impacts don't exceed our ability to cope, and that means what it always means in security: Methodical, purposeful, and determined actions. 

What are those tasked with protecting corporate networks to do? If we move too quickly, perhaps the changes we make will have worse outcomes than being offline. Would 1,000 employees suddenly hitting the VPN crush the infrastructure? Do we have a strategy to roll out two-factor to everyone? How will staff even log in? Personal computers via RDP? Ooof.

As someone who makes a living taking advantage of rush jobs and sloppy IT handiwork, urgently configured, patched, and deployed VPNs make my job a breeze. Disable two-factor authentication (2FA) and I'm in heaven. 

So, how do we keep our adversaries at bay, while balancing the survival of the business? 

First step, get stakeholder buy-in to take a measured and methodical approach to manage risk as you transition to a remote work environment. Have a candid conversation with your business leaders about the risks of going too fast and not taking appropriate precautions. Educate stakeholders on the risks of moving everyone overnight to the VPN, and ask them to prioritize what's required now, and what can wait (create cohorts of users based on those that need access first, and so on). 

Once you've got buy-in, focus on nailing the fundamentals, and that means going beyond patching known VPN vulns. There are always unpatchable weaknesses and non-public issues that hackers can exploit. To mitigate these unknowns, companies need to look at the fundamentals.  

  • Like any disaster scenario, nothing matters if you can’t get critical functions working. Get the VPNs up, but try not to cut too many corners (change the default password!). Critical users doing their jobs effectively is better than a horde of half-functioning folks.
  • Segment your network. Make sure your VPN lands in a DMZ and can't talk to everything. If users are remoting into a desktop, they don't need access to backend databases or infrastructure.
  • Least privilege should be your standard. Your marketer most likely doesn't need access to your infrastructure.
  • Visibility and vigilant monitoring: When an employee's credentials are compromised, you want a fighting chance of catching it early and responding well. If you're a responder accustomed to confiscating the box, plan in advance to conduct an investigation with remote users, and get visibility in place before you need it.
  • Educate your users. Make sure they understand the new risks and remind them, "Hey, don't click links for outbreak maps in your email, okay?"

If you can get privileges locked down, some basic segmentation in place, and some visibility, then at least your team has a fighting chance to keep the hackers out while 2FA rolls out. At least your MSSP has some data they can respond with.

Extreme times, extreme measures… sure. And yes, VPNs are incredibly valuable, so use them properly. But don't expect to turn something on overnight and get it right; that's bound to lead to mistakes that your adversary can exploit. But move with intention and engage in ways that don't make the world worse. The continuity of the business may require compromise to specific security procedures, but take reasonable steps to reduce the security risk to your organization, and make it a dialogue with the business so the risks are understood.

Related Content:

Check out The Edge, Dark Reading's new section for features, threat data, and in-depth perspectives. Today's featured story: " How to Evict Attackers Living Off Your Land."

David Wolpoff (Moose) is co-founder and CTO of Randori. Moose's background is in digital forensics, vulnerability research, reverse engineering and embedded electronic design. Before Randori, Moose ran "Hacker on Retainer," where he conducted determined adversary attacks for ... View Full Bio
 

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