How to Prepare for Ransomware Attacks
Ransomware attacks continue to increase. Bad
actors have changed tactics, and are using techniques that are more
sophisticated and targeted. To help protect the organization from ransomware,
security and risk management leaders need to look beyond just the endpoints.
Overview
Key Findings
- Phishing,
remote attacks on public facing infrastructure, and
unauthorized remote desktop connections continue to be the
primary sources of infiltration for ransomware. This has been exacerbated
by the growth in remote work resulting from the pandemic.
- Bad
actors are mining exfiltrated data to identify other potential sources for
revenue.
- The
cost of recovery and resulting downtime in the aftermath of a ransomware
attack, and the cost of the reputational damage, can amount to 10
times the amount of the ransom itself.
Recommendations
Security and risk management leaders
responsible for endpoint and network security must focus on all three stages of
a ransomware attack:
- Get ready
for ransomware attacks by constructing a preincident prevention
strategy that includes endpoint protection, data protection, immutable
backup, asset management, end-user awareness training and strong identity
and access management.
- Implement
detection measures by deploying behavioral-anomaly-based detection
technologies to identify ransomware attacks.
- Build postincident response
procedures by training staff and scheduling regular training
exercises. This should include development of a ransomware response
playbook to augment existing incident response plans with the
addition of recovery options (such as endpoint rollback, bare metal
restore and decryption processes).
Introduction
Ransomware
continues to pose a significant risk to organizations. Recent attacks have
evolved from autospreading attacks, such as Maze and Ryuk, to
more targeted human-operated campaigns, which attack organizations, rather than individual endpoints.
This often results in double or triple extortion tactics. The impact that these
attacks have on organizations has increased to the point where some
organizations have gone out of business, and, in the case of healthcare,
lives have been put at risk. Security and risk management (SRM) leaders
need to adapt to these changes and look beyond just endpoint security controls
to protect against ransomware.
Recent
ransomware campaigns, such as REvil and Ryuk, have become
“human-operated ransomware,” where the attack is controlled by an operator,
rather than spreading automatically. Such attacks often take advantage of
well-known security weaknesses to gain access. For example, a number of recent
ransomware incidents are thought to have started with poorly configured or
vulnerable remote desktop protocol (RDP) configurations or poor identity and
access management (IAM) practices. Previously compromised credentials are
also being used to gain access to systems. These can be obtained through
initial access brokers or other dark web data dumps.
Once
inside, the attacker will move around in the network, identify the valuable
data, and assess the security controls used, often disabling endpoint
protection tools and deleting backups. Then, when the data has been identified,
it can be uploaded and later used for extortion (doxxing), and the ransomware
will be launched to encrypt the data. The median dwell time between the
first evidence of malicious activity and the deployment of ransomware is five
days. The goal is to maximize the likelihood of the ransom being paid,
which often means that the attack includes threats to make data public if the
ransom isn’t paid quickly.
Analysis
Construct a Preincident Preparation Strategy
SRM leaders
should work under the assumption that a ransomware attack will be successful,
and ensure that the organization is prepared to detect as early as
possible and recover as quickly as possible. Your ability to quickly
detect and contain a ransomware attack will have the biggest impact on any
outage or disruption that is caused.
The first
and most common question is, “should the ransom be
paid?”. Ultimately, this has to be a business decision. It needs to be
made at an executive or board level, with legal advice. Law enforcement
agencies recommend not paying, because it encourages continued criminal
activity. In some cases, paying the ransom could be seen as illegal, because it provides funding for criminal activity. Regardless, the
discussion needs to occur. There are several examples of
organizations that worked with law enforcement during a ransomware incident and
made the decision to pay because it was the best option for their business. A
recent survey found that 46% of companies ultimately pay the ransom.
Should
payment be a consideration, it is important to establish a governance and legal
process that includes the CEO, the board and key operational staff. It is
not recommended for organizations to take on the negotiation with the bad
actors without guidance. This is typically done by a third-party negotiation
service provider. In addition to being the primary negotiator, they also have
the ability to facilitate payments and in many cases remove the requirement for
the business to maintain cryptocurrency.
A
word of caution — even if the ransom is paid, there is no guarantee that your
data will be recovered. The encrypted files can be unrecoverable due to data
corruption during the encryption process.
Build Peri-incident and Postincident Response
Procedures by Training Staff and Scheduling Drills
SRM leaders
must ultimately be prepared for a ransomware attack to be successful and have
plans, processes and procedures in place. These plans need to include the IT
aspects, and communication plans for both internal staff and partners and
suppliers. It is important that SRM leaders quickly and clearly communicate the
issue. Provide regular updates on status and when systems will be recovered to
the point where systems are usable. Several cyber crisis simulation tools can
help identify gaps in procedures, roles and responsibilities.
These plans
will vary, based on the extent and success of a ransomware attack. It may only
be a small part of an organization, and the impact could be minimal. For larger
attacks, the impact may go beyond the organization to customers and partners.
As part of the preparation, running regular fire drills or table-top exercises
to rehearse a response can be beneficial. Ideally these exercises will cover
both the business and technical response activities required.
Once
recovery is in progress, collect enough information to understand the root
cause of the attack and understand which controls failed or weren’t in place.
Again, specialist digital forensics and incident response services play an
important role in this analysis. Once systems are recovered, it is critical to
implement the lessons learned and feed them back into the preparation phase.
Develop a Ransomware Playbook
Ransomware
is unlike any other security incident. It puts affected organizations on a
countdown timer. Any delay in the decision making process introduces additional
risk.
During
a ransomware event, business leaders will be forced to make big decisions with
very little information.
Additional
roles — such as a timekeeper — need to be assigned. The timekeeper is
responsible for tracking the remaining response time according to the
ransomware demand. Losing track of the time can result in public disclosure of
data and an increase in the ransom amount.
Guidance on
making a “pay/no-pay” decision should also be included. Third-party services
such as ransomware negotiation companies need to be identified and requisite
contact information made available. A ransomware playbook provides the
prescriptive guidance to address a ransomware event.
Be honest
with yourself and understand your organization’s limitations for monitoring,
detecting and responding to security incidents. Many organizations will need
assistance to help mitigate, detect and recover from an attack. Specialist
incident response teams can play an important role, and having an incident
response retainer in place can reduce the cost and speed of the response.
The
tactical recovery steps will vary, depending on the organization and the extent
of the ransomware, but will involve:
- Recovery of data from backups,
including verifying the integrity of those backups and understanding what
data, if any, has been lost.
- Once compromised, using EPPs
and EDR, as well as MTD solutions, as part of the remediation response to
remove and isolate the threat. Recovery goes beyond recovering the data.
Infected machines may be “locked” and may require physical access. During
the preparation phase, it’s important to understand and plan for how this
would be achieved.
- Validation of the integrity of
a device before it is allowed back onto the network.
- Updating or removing
compromised credentials. Without this, the attacker will be able to gain
entry again.
- Performing a thorough root
cause analysis of what happened and how — including accounting for any
data that has been exfiltrated (doxxing). Doxxing occurs when bad actors
threaten to release stolen information. This is increasingly becoming a
secondary method of extortion if a victim decides not to pay the ransom.
- Bringing in experts — you
cannot do it alone.