A new paper on anti-ransomware research from the team at the University of Kent is now published:
Jamie Pont, Osama Abu Oun, Calvin Brierley, Budi Arief, Julio Hernandez-Castro, “A Roadmap for Improving the Impact of Anti-Ransomware Research”, In: A. Askarov, R. Hansen, W. Rafnsson (eds) Secure IT Systems, NordSec 2019, Lecture Notes in Computer Science, vol 11875, Springer, Cham, pp. 137-154, 2019.
A ransomware campaign that targeted 23 US cities across Texas has raised serious concerns about the vulnerability of local governments and public services to cyber-attacks. These events come not long after similar attacks on governmental and business organisations in Indiana, Florida and elsewhere. They reflect a general shift in ransomware tactics from “spray and pray” attacks on large numbers of individual consumers, to “big game hunting”, which targets organisations, usually through people in positions of power.
A recent report from cyber-security firm Malwarebytes found a 363% increase in ransomware detections against businesses and organisations (as opposed to individuals) from 2018 to 2019. Put simply, cyber-criminals see an opportunity to extort far more money from organisations than individuals. Although the majority of ransomware attacks were found to occur in the US, local governments around the world are equally vulnerable.
Ransomware usually spreads via phishing emails or links to infected websites, relying on human error to gain access to systems. As its name suggests, ransomware is designed to block access to data, systems or services until a ransom is paid. At a technical level, cities tend to be fairly easy targets because they often have bespoke operating systems, with parts that are old and out-of-date, as well as ineffective back-up measures.
Cities also tend to lack system-wide security policies, so if cyber-criminals gain entry through one system, they can then access others and wreak havoc by freezing essential data and preventing the delivery of services. But even if organisations have improved their technical security, my research with my colleague Lena Connolly has found that few put equal emphasis on training employees to identify and resist attacks.
Employees in many small and medium-sized organisations, like local governments, often do not recognise their organisation’s true commercial value to criminals, and commonly think they are unlikely to be targeted. As a result, they might also develop bad habits – such as using work systems for personal reasons – which can increase vulnerability.
Offenders will do their homework before launching an attack, in order to create the most severe disruption they possibly can. After all, the greater the pressure to pay the ransom, the higher they can set the tariff.
Attackers identify key individuals to target and seek out vulnerabilities such as computers which have been left switched on outside of working hours, or have not been updated. Once they’ve worked out who to target, cyber-criminals deploy “social engineering” techniques, such as phishing, which psychologically manipulate victims into opening an email attachment or clicking on a link, which allows the ransomware programme into the organisation’s operating system.
To pay or not to pay?
Whether or not to pay the ransom is not a straightforward decision for city authorities with vital public services on the line. Most policing agencies instruct victims not to pay, but as Mayor Stephen Witt of Lake City, Florida, put it after his ward was targeted:
With your heart, you really don’t want to pay these guys. But, dollars and cents, representing the citizens, that was the right thing to do.
Another problem is that ransomware is not always deployed to extort money – so paying the ransom doesn’t guarantee that data will be restored. Attackers can have varying motives, skills and resources – working out their motive (often with very little information) is therefore crucial.
Rather than simply making money using ransomware, some cyber-criminals might seek to disable market competitors who provide competing goods or services. Or, they may use the attacks for political gain, to reduce public confidence in a local government’s ability to deliver essential services. In such cases, the data is unlikely ever to be restored, even if the ransom is paid.
Many cities are insured against attacks, and insurers often pay the ransom to retrieve stolen data – sometimes employing third party negotiators, against national advice. Ironically, the knowledge that cyber-criminals are likely to get paid justifies the time they spend researching their target’s weaknesses, and leaves the door open for repeat attacks. This was one of the reasons why cyber-criminals changed tactics and started targeting organisations in the first place.
This leaves city authorities a difficult choice, between paying to restore essential data and services (and encouraging cybercriminals) or admitting their systems have been compromised and facing up to social and political backlash. Even so, there are some measures city authorities can take to protect themselves, and their citizens, from ransomware.
Today, authorities need to assume that it’s a matter of when – not if – an attack will happen. They should install back up systems for protected data that have the capacity to replace infected operating systems and databases if need be. For example, in the UK, research found that 27% of local government organisations were targets of ransomware in 2017. Yet 70% of their 430 respondents had backup systems in place, in preparation for the EU’s General Data Protection Regulation (GDPR), and could therefore recover from a ransomware attack much faster than their counterparts in the US.
Local authorities need to separate their data systems where possible and install appropriate levels of security. They also need to train employees about the nature of the threat and the impacts of their own actions when working within the organisation’s systems. They should also be aware of international schemes to prevent and mitigate ransomware (such as nomoreransom.org) – which provide advice and publish the keys to some ransomware online.
Public organisations must be able to think quickly and adapt to these new security threats – especially since cyber-criminals are always coming up with new techniques. Local governments need to be prepared to simultaneously prevent cyber-attacks, mitigate their effects when they do happen and bring cyber-criminals to justice.
A new paper under this title has just been published by Lena Connolly and David Wall in the journal Computers and Security.
Here is a summary of Connolly, A, and Wall, D.S. (2019) ‘The Rise of Crypto-Ransomware in a Changing Cybercrime Landscape: Taxonomising Countermeasures, Computers and Security. Available online, https://doi.org/10.1016/j.cose.2019.101568
Each year the
increasing adaptivity of cybercriminals maintains ransomware’s position as a
major cybersecurity threat. Evidence of this shift can be seen in its evolution
from ‘scareware’ and ‘locker’ scams through to crypto-ransomware attacks. Whereas
‘scareware’ used to bully victims into paying a fee to remove bad files, ‘lockers’
froze the computer until a ransom payment was made for a release code. Crypto-ransomware,
in contrast, encrypts the actual data on the victim’s computer until a ransom
payment is made (usually in bitcoin) to release it. In more recent malicious
cases there is no release key, it is used as an attack weapon to permanently
fry and disable the victims’ data, which can be devastating for the
organisation involved and even more disastrous if it delivers national infrastructure.
and secondary empirical sources, this article draws upon candid in-depth
interviews with 26 victims, practitioners and policy makers to explore their reactions
to the shift in the ransomware landscape. Our research indicates that a subtle ecosystem
of social and technical factors makes crypto-ransomware especially harmful, as
a consequence there is no simple remedy, no silver bullet, for such a complex
threat like crypto-ransomware. The attackers are increasingly doing their
homework on organisations before they attack and hence, are extremely adaptive
in both delivering their ever-developing ransomware. They are also tailoring
their attack vectors to exploit existing weaknesses within organisations.
Successful attacks combine scientific and social methods to employ a variety of
‘social’ techniques to get the malware onto the victims operating system. Techniques
that include, for example, psychological trickery, profiling staff, exploiting technical
shortcomings, areas of neglect by senior management and a shortage of skilled,
dedicated and adaptive front-line managers – basically any opportunity available.
illustrate the nuanced relationship between technological and social aspects of
crypto-ransomware and the organisational setting, indicating that a
multi-layered approach is required to protect organisations and make them more
resilient to ransomware attacks. Attacks, which are increasingly shifting from
simple economic crimes of extortion, to disrupting and even destroying
organisations and the services they provide. While the cybersecurity industry
has responded to progressively serious ransomware threats with a similar degree
of adaptiveness to the offenders, they have tended to focus more upon
scientific ‘technical’ factors than the ‘non-technical’, social, aspects of
ransomware. So, these observations suggest that organisations need to continually
improve their security game more frequently and be as adaptive as the criminals
in their responses to attacks. In order to achieve this goal, we developed a taxonomy
of crypto-ransomware countermeasures that identifies a range of response tools, which arethe socio-technical
measures and controls necessary for organisations to implement in order to
respond to crypto-ransomware effectively. We then, identified the enablers
of change, the groups of employees, such as front-line managers and senior
management, who must implement the response tools to ensure the organisation is
prepared for cyber-attacks.
findings, therefore, will not only assist Police Officers working in Cybercrime
Units in further understanding the perspective of the victims and also the
impacts of crypto-ransomware. But, they have important practical implications
for IT and Security managers and their organisations more generally (some of
which are police). The taxonomy provides a blueprint for systematising security
measures to protect organisations against crypto-ransomware attacks. Managers need
to select controls appropriate to their specific organisational settings, for
example, the ‘business-use only’ of IT resources is necessary in some
organisations, such as commercial organisations, while not practical in others
such as research institutions. Also, face-to-face security training, for
example, may be more possible and effective in smaller organisations than large
ones. The taxonomy also underlines the importance of embedding appropriate ‘social’
based controls in organisational cultures rather than simply focus upon
technical measures. This is because, as indicated above, inappropriate
measures, skills and support led to incidents occurring, some of which were
particularly devastating. Furthermore, the taxonomy underlines the crucial role
that mid-level managers play in responding to crypto-ransomware threats.
set for competent front-line management also goes beyond being security and
IT-savvy, to becoming organisationally adaptive and to think like ‘the enemy’. Security
professionals are not only required to be influential mid-level leaders who can
change attitudes and behaviours in organisations by cultivating certain
cultural traits. They have to understand both cultural factors and human
behaviour and express this understanding in practice to succeed in their role. In
return, senior management must be IT-competent and be effective in overseeing the
IT functions of their organisation. Senior managers represent an important part
of the security chain in organisations and need to support the efforts of
mid-managers. Ultimately, both levels have to respect each other’s position to
work together co-own the problem to co-produce the solution – something that is
easy to say but hard to put into practice. Our future plan is to convert the
taxonomy into a more user-friendly tool, similar to the Cyber Essentials
Once a piece of ransomware has got hold of your valuable information, there is very little you can do to get it back other than accede to the attacker’s demands. Ransomware, a type of malware that holds a computer to ransom, has become particularly prevalent in the past few years and virtually unbreakable encryption has made it an even more powerful force.
Ransomware is typically delivered by powerful botnets used to send out millions of malicious emails to randomly targeted victims. These aim to extort relatively small amounts of money (normally £300-£500, but more in recent times) from as many victims as possible. But according to police officers we have interviewed from UK cybercrime units, ransomware attacks are becoming increasingly targeted at high-value victims. These are usually businesses that can afford to pay very large sums of money, up to £1,000,000 to get their data back.
In 2017 and 2018 there was a rise in such targeted ransomware attacks on UK businesses. Attackers increasingly use software to search for vulnerable computers and servers and then use various techniques to penetrate them. Most commonly, perpetrators use brute force attacks (using software to repeatedly try different passwords to find the right one), often on systems that let you operate computers remotely.
If the attackers gain access, they will try to infect other machines on the network and gather essential information about the company’s business operations, IT infrastructure and further potential vulnerabilities. These vulnerabilities can include when networks are not effectively segregated into different parts, or are not designed in a way that makes them easy to monitor (network visibility), or have weak administration passwords.
They then upload the ransomware, which encrypts valuable data and sends a ransom note. Using information such as the firm’s size, turnover and profits, the attackers will then estimate the amount the company can afford and tailor their ransom demand accordingly. Payment is typically requested in cryptocurrency and usually between 35 and 100 bitcoins (value at time of publication £100,000–£288,000).
According to the police officers we spoke to, another popular attack method is “spear phishing” or “big game hunting”. This involves researching specific people who handle finances in a company and sending them an email that pretends to be from another employee. The email will fabricate a story that encourages the recipient to open an attachment, normally a Word or Excel document containing malicious code.
These kind of targeted attacks are typically carried out by professional groups solely motivated by profit, though some attacks seek to disrupt businesses or infrastructure. These criminal groups are highly organised and their activities constantly evolve. They are methodical, meticulous and creative in extorting money.
For example, traditional ransomware attacks ask for a fixed amount as part of an initial intimidating message, sometimes accompanied by a countdown clock. But in more targeted attacks, perpetrators typically drop a “proof of life” file onto the victim’s computer to demonstrate that they control the data. They will also send contact and payment details for release of the data, but also open up a tough negotiation process, which is sometimes automated, to extract as much money as possible.
According to the police, the criminals usually prefer to target fully-digitised businesses that rely highly on IT and data. They tend to favour small and medium-sized companies and avoid large corporations that have more advanced security. Big firms are also more likely to attract media attention, which could lead to increased police interest and significant disruptions to the criminal operations.
How to protect yourself
So what can be done to fight back against these attacks? Our work is part of the multi-university research project EMPHASIS, which studies the economic, social and psychological impact of ransomware. (As yet unpublished) data collected by EMPHASIS indicates that weak cybersecurity in the affected organisations is the main reason why cybercriminals have been so successful in extorting money from them.
One way to improve this situation would be to better protect remote computer access. This could be done by disabling the system when it’s not in use, and using stronger passwords and two-step authentication (when a second, specially generated code is needed to login alongside a password). Or alternatively switching to a virtual private network, which connects machines via the internet as if they were in a private network.
When we interviewed cybercrime researcher Bob McArdle from IT security firm Trend Micro, he advised that email filters and anti-virus software containing dedicated ransomware protection are vital. Companies should also regularly backup their data so it doesn’t matter if someone seizes the original. Backups must be tested and stored in locations that are inaccessible to ransomware.
These kind of controls are crucial because ransomware attacks tend to leave very little evidence and so are inherently difficult to investigate. As such, targeted ransomware attacks are not going to stop any time soon, and attackers are only likely to get more sophisticated in their methods. Attackers are highly adaptive so companies will have to respond just as smartly.
A new article based on the EMPHASIS work has been published in the Crime Science journal:
Gavin Hull, Henna John, Budi Arief, “Ransomware Deployment Methods and Analysis: Views from a Predictive Model and Human Responses”, Crime Science 8(2), 2019.
The full article can be found at https://rdcu.be/bmtVa