As the frequency and intensity of ransomware attacks increase, one thing is becoming abundantly clear: organizations can do more to protect themselves. Unfortunately, most organizations are dropping the ball. Most victims receive adequate warning of potential vulnerabilities yet are woefully unprepared to recover when they are hit. Here are just a few recent examples of both prevention and incident response failures:
- Two months before the city of Atlanta was hit by ransomware in 2018, an audit identified over 1,500 severe security vulnerabilities.
- Before the city of Baltimore suffered multiple weeks of downtime due to a ransomware attack in 2019, a risk assessment identified a severe vulnerability due to servers running an outdated operating system (and therefore lacking the latest security patches) and insufficient backups to restore those servers, if necessary.
- Honda was attacked this past June, and public access to Remote Desktop Protocol (RDP) for some machines may have been the attack vector leveraged by hackers. Complicating matters further, there was a lack of adequate network segmentation.
Other notable recent victims include Travelex, Blackbaud, and Garmin. In all these examples, these are large organizations that should have very mature security profiles. So, what’s the problem?
Three common mistakes lead to inadequate prevention and ineffective response, and they are committed by organizations of all sizes:
1. Failing to present risk in business terms, which is crucial to persuading business leaders to provide appropriate funding and policy buy-in.
2. Not going deep enough in how you test your ransomware readiness.
3. Insufficient DR planning that fails to account for a ransomware threat that could infect your backups.
Common mistake #1 – Failing to present security risk in business terms to get funding and policies
I was reminded of just how easy it is to bypass basic security (e.g., firewalls, email security gateways, and anti-malware solutions) when I recently watched a ransomware attack simulation: the initial pre-ransomware payload got a foot in the door, followed by techniques such as reverse DNS lookups to identify an Active Directory service, that has the necessary privileges to really do some damage, and finally Kerberoasting to take control.
No organization is bulletproof, but attacks take time – which means early detection with more advanced intrusion detection and a series of roadblocks for hackers to overcome (e.g., greater network segmentation, appropriate end-user restrictions, etc.) are crucial for prevention.
This is not news to security practitioners. But convincing business leaders to make additional security investments is another challenge altogether.
How to fix mistake #1: Quantify business impact to enable an informed cost-based business decision
Tighter security controls (via technology and policy) are friction for the business. And while no business leader wants to fall victim to ransomware, budgets are not unlimited.
To justify the extra cost and tighter controls, you need to make a business case that presents not just risk, but also quantifiable business impact. Help senior leadership compare apples to apples – in this case, the cost of improved security (capex and potential productivity friction) vs. the cost of a security breach (the direct cost of extended downtime and long-term cost of reputational damage).
Assessing business impact need not be onerous. Fairly accurate impact assessments of critical systems can easily be completed in one day. Focus on a few key applications and datasets to get a representative sample, and get a rough estimate of cost, goodwill, compliance, and/or health & safety impacts, depending on your organization. You don’t have to be exact at this stage to recognize the potential for a critical impact.
Below is an example of the resulting key talking points for a presentation to senior leadership:
Source: Info-Tech Research Group, Business Impact Analysis Summary Example, 2020
Common mistake #2 – Not going deep enough in testing ransomware readiness
If you aren’t already engaged in penetration testing to validate security technology and configuration, start now. If you can’t secure funding, re-read How to fix mistake #1.
Where organizations go wrong is stopping at penetration testing and not validating the end-to-end incident response. This is especially critical for larger organizations that need to quickly coordinate assessment, containment, and recovery with multiple teams.
How to fix mistake #2: Run in-depth tabletop planning exercises to cover a range of what-if scenarios
The problem with most tabletop planning exercises is that they are designed to simply validate your existing incident response plans (IRP).
Instead, dive into how an attack might take place and what actions you would take to detect, contain, and recover from the attack. For example, where your IRP says check for other infected systems, get specific in how that would happen. What tools would you use? What data would you review? What patterns would you look for?
It is always an eye-opener when we run tabletop planning with our clients. I’ve yet to come across a client that had a perfect incident response plan. Even organizations with a mature security profile and documented response plans often find gaps such as:
- Poor coordination between security and infrastructure staff, with unclear handoffs during the assessment phase.
- Existing tools aren’t fully leveraged (e.g., configuring auto-contain features).
- Limited visibility into some systems (e.g., IoT devices and legacy systems).
Common mistake #3 – Backup strategies and DR plans don’t account for ransomware scenarios
Snapshots and standard daily backups on rewritable media, as in the example below, just aren’t good enough:
Source: Info-Tech Research Group, Outdated Backup Strategy Example, 2020
The ultimate safety net if hackers get in is your ability to restore from backup or failover to a clean standby site/system.
However, a key goal of a ransomware attack is to disable your ability to recover – that means targeting backups and standby systems, not just the primary data. If you’re not explicitly guarding against ransomware all the time, the money you’ve invested to minimize data loss due to traditional IT outages – from drive failures to hurricanes – becomes meaningless.
How to fix mistake #3: Apply defense-in-depth to your backup and DR strategy
The philosophy of defense-in-depth is best practice for security, and the same philosophy needs to be applied to your backups and recovery capabilities.
Defense-in-depth is not just about trying to catch what slips through the cracks of your perimeter security. It’s also about buying time to detect, contain, and recover from the attack.
Achieve defense-in-depth with the following approach:
1. Create multiple restore points so that you can be more granular with your rollback and not lose as much data.
2. Reduce the risk of infected backups by using different storage media (e.g., disk, NAS, and/or tape) and backup locations (i.e., offsite backups). If you can make the attackers jump through more hoops, it gives you a greater chance of detecting the attack before it infects all of your backups. Start with your most critical data and design a solution that considers business need, cost, and risk tolerance.
3. Invest in solutions that generate immutable backups. Most leading backup solutions offer options to ensure backups are immutable (i.e., can’t be altered after they’re written). Expect the cost to be higher, of course, so again consider business impact when deciding what needs higher levels of protection.
Summary: Ransomware security planning
Ransomware attacks can be sophisticated, basic security practices just aren’t good enough. Get buy-in from senior leadership on what it takes to be ransomware-ready by presenting not just the risk of attack, but the potential extensive business impact. Assume you’ll get hit, be ready to respond quickly, test realistically, and update your DR strategy to encompass this fast-evolving threat.
from Help Net Security https://ift.tt/33zM33M
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