Kraken Cryptor Ransomware

First observed in August 2018, Kraken Cryptor is a ransomware tool that is delivered to users disguised as a legitimate anti-virus application.

Threat ID:: CC-2673
Category:: Ransomware
Threat Severity:: Low
Threat Vector:: Download
Published:: 20 September 2018 12:00 AM

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Summary

First observed in August 2018, Kraken Cryptor is a ransomware tool that is delivered to users disguised as a legitimate anti-virus application.

Affected platforms

The following platforms are known to be affected:

Microsoft Windows

Microsoft Windows - All versions

Threat details

Kraken Cryptor was initially distributed as a malicious executable file hosted on the SuperAntiSpyware website, an anti-virus and -malware program. Both the real and malicious versions were available for download until late August 2018, presumably when the owners of the site were notified, at which point they removed the malicious file. However, numerous other download portal sites continue to host the malicious version.

Once installed, Kraken Cryptor will check the system language of the infected device before deployment. If the languages of any 17, mainly former USSR, countries are detected it will not proceed any further. It will then attempt to close a number of processes and delete or disable Windows recovery services before encrypting all available files with extensions that match a hard-coded list. Kraken Cryptor will also use the SDelete tool to overwrite all free space on the affected drives, possibly to hinder file recovery.

Threat updates

Date	Update
8 Oct 2018	Delivery update Kraken Cryptor is now being delivered by the Fallout exploit kit.

Remediation steps

Type	Step
	If a device on your network becomes infected with ransomware it will begin encrypting local machine files and files on any network the logged-in user has permission to access. For system administration accounts this may include backup storage locations. To avoid becoming infected with ransomware, ensure that: A robust program of education and awareness training is delivered to users to ensure they don’t open attachments or follow links within unsolicited emails. All operating systems, anti-virus and other security products are kept up to date. All day to day computer activities such as email and internet are performed using non-administrative accounts and that permissions are always assigned based on the principle of least privilege. Your organisation adopts a holistic all-round approach to Cyber Security as advocated by the 10 Steps to Cyber Security. Identifying the source of infection: Identifying the affected device and disconnecting or quarantining it from the network is essential to damage limitation. Users should immediately report infections to their IT support provider, disconnect their network cable and power the computer down. File auditing should be enabled, and file server logs should be monitored to detect signs of unauthorised encryption and allow the source of encryption to be identified (i.e. the infected device). To limit the damage of ransomware and enable recovery: All critical data must be backed up, and these backups must be sufficiently protected/kept out of reach of ransomware. Multiple backups should be created including at least one off-network backup (e.g. to tape). The only guaranteed way to recover from a ransomware infection is to restore all affected files from their most recent backup.

Type

Step

If a device on your network becomes infected with ransomware it will begin encrypting local machine files and files on any network the logged-in user has permission to access. For system administration accounts this may include backup storage locations.

To avoid becoming infected with ransomware, ensure that:

A robust program of education and awareness training is delivered to users to ensure they don’t open attachments or follow links within unsolicited emails.
All operating systems, anti-virus and other security products are kept up to date.
All day to day computer activities such as email and internet are performed using non-administrative accounts and that permissions are always assigned based on the principle of least privilege.
Your organisation adopts a holistic all-round approach to Cyber Security as advocated by the 10 Steps to Cyber Security.

Identifying the source of infection:
Identifying the affected device and disconnecting or quarantining it from the network is essential to damage limitation.

Users should immediately report infections to their IT support provider, disconnect their network cable and power the computer down.
File auditing should be enabled, and file server logs should be monitored to detect signs of unauthorised encryption and allow the source of encryption to be identified (i.e. the infected device).

To limit the damage of ransomware and enable recovery:
All critical data must be backed up, and these backups must be sufficiently protected/kept out of reach of ransomware.

Multiple backups should be created including at least one off-network backup (e.g. to tape).
The only guaranteed way to recover from a ransomware infection is to restore all affected files from their most recent backup.

Last edited: 11 January 2022 3:45 pm