The SamSam ransomware attacks are continuing and the threat actors behind the campaign are showing no sign of stopping. So far in 2018 there have been at least 10 attacks in the United States, although many more may have gone unreported. Most of the known attacks have hit government agencies, municipalities, and healthcare organizations – all of whom are required to disclose attacks.
The attacks have caused massive disruption, taking computers, servers, and information systems out of action for several days to several weeks. Faced with the prospect of continued disruption to essential business processes, some organizations have chosen to pay the ransom – a risky strategy since there is no guarantee that the keys to unlock the encryption will work or even be supplied.
Others have refused to be extorted, often at great cost. One U.S. healthcare provider, Erie County Medical Center, took six weeks to fully recover from the attack. Mitigating the attack has cost several million dollars.
Multiple SamSam ransomware attacks are possible as the Colorado Department of Transportation discovered. After recovering from an attack in February, a second attack occurred in March.
It is not only financial harm that is caused by the attacks. Another hospital was attacked, and its outpatient clinic and three physician hospitals were unable to view histories or schedule appointments. The ransomware attack on the electronic medical record provider AllScripts saw its EMR systems taken out of action for several days. During that time, around 1,500 medical centers were unable to access patient health records resulting in many cancellations of non-critical medical appointments.
The March SamSam ransomware attack on the City of Atlanta brought many government services to a grinding halt. The extensive attack forced the shutdown of many systems, many of which remained inaccessible for six days. Bills and parking tickets couldn’t be paid and court proceedings had to be cancelled. The huge backlog of work continued to cause delays when systems were restored.
While the SamSam ransomware attacks have been concentrated on just a few industry sectors, the attacks are not necessarily targeted. What the victims have in common is they have been found to have easily exploitable vulnerabilities on public facing servers. They were attacked because mistakes had been made, vulnerabilities had not been patched promptly, and weak passwords had been set.
The threat actors behind the latest SamSam ransomware attacks have not been confirmed, although researchers at Secureworks believe the attacks are being conducted by the Gold LOWELL threat group. It is not known whether they are a defined group or a network of closely affiliated threat actors. What is known, whether it is GOLD LOWELL or other group, is they are largely staying under the radar.
What is more certain is the SamSam ransomware attacks will continue. In the first four weeks of January, the Bitcoin wallet used by the attackers showed $325,000 of ransom payments had been paid. The total in April is likely to be substantially higher. Hancock Health, one of two Indiana hospitals attacked this year, has confirmed that it paid a ransom demand of approximately $55,000 for the keys to unlock the encryption. As long as the attacks remain profitable and the threat actors can stay under the radar, there is no incentive to stop.
In contrast to many threat actors that use phishing emails and spam messages to deliver ransomware downloaders, this group exploits vulnerabilities on public-facing servers. Access is gained to the network, the attackers spend time navigating the network and moving laterally, before the ransomware payload is finally deployed. Detecting network intrusions quickly may prevent file encryption, or at least limit the damage caused.
The ongoing campaign has now prompted the U.S. Department of Health and Human Services’ Healthcare Cybersecurity Integration and Communications Center (HCCIC) to issue a warning to healthcare organizations about the continued threat of attacks. Healthcare organizations should heed the advice of the HCCIC and not only implement defences to block attacks but also to prepare for the worst. If contingency plans are made and incident response procedures are developed in advance, disruption and cost will be kept to a minimum.
That advice from the HCCIC to prevent SamSam ransomware attacks is:
- Conduct vulnerability scans and risk assessments to identify potential vulnerabilities
- Ensure those vulnerabilities are remediated
- Ensure patches are applied promptly
- Use strong usernames and passwords and two-factor authentication
- Limit the number of users who can login to remote desktop solutions
- Restrict access to RDP behind firewalls and use a VPN or RDP gateway
- Use rate limiting to stop brute force attacks
- Ensure backups are made for all data to allow recovery without paying the ransom and make sure those backups are secured
- Develop a contingency plan to ensure that the business can continue to function while the attack is mitigated
- Develop procedures that can easily be followed in the event of a ransomware attack
- Implement defenses capable of detecting attacks quickly when they occur
- Conduct annual penetration tests to identify vulnerabilities and ensure those vulnerabilities are rapidly addressed