Scarab Ransomware

Scarab is based on a proof-of-concept ransomware called HiddenTear and is marked as being less sophisticated than more popular variants like Locky. It is delivered via phishing emails using a .7z attachment containing a VBScript dropper.

Threat ID:: CC-1829
Category:: Ransomware, Botnet
Threat Severity:: Medium
Threat Vector:: Phishing
Published:: 30 November 2017 12:00 AM

Report a cyber attack: call 0300 303 5222 or email [email protected]

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Summary

Affected platforms

The following platforms are known to be affected:

Microsoft Windows

Microsoft Windows - All Versions

Threat details

It is delivered via phishing emails using a .7z attachment containing a VBScript dropper. Once files are encrypted with a ‘[[email protected]].scarab’ extension a ransom note is dropped in each directory demanding an unspecified amount of BitCoin be sent to the provided email address. Scarab has been delivered using the Necurs botnet.

Detection rates for Scarab in anti-virus suites are also very high, minimising the risk it poses to organisations.

Threat updates

Date	Update
2 Feb 2018	Updates A new variant has been observed named 'Scarabey,' which is being distributed both via Remote Desktop Protocol (RDP) and via manual transfer onto servers and systems. Scarabey targets Russian-speaking regions as the ransom note is written in Russian. To persuade victims to pay the ransom, it falsely claims to use server-side encryption and to delete files if payment is not made quickly. To help prevent an infection, it is recommended that Internet-facing RDP ports are closed or appropriately monitored. The indicators of compromise above have been updated.

Date

Update

2 Feb 2018

Updates

A new variant has been observed named 'Scarabey,' which is being distributed both via Remote Desktop Protocol (RDP) and via manual transfer onto servers and systems. Scarabey targets Russian-speaking regions as the ransom note is written in Russian. To persuade victims to pay the ransom, it falsely claims to use server-side encryption and to delete files if payment is not made quickly. To help prevent an infection, it is recommended that Internet-facing RDP ports are closed or appropriately monitored. The indicators of compromise above have been updated.

Remediation steps

Type	Step
	If a computer 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, antivirus 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 on the basis 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 infected machine and unplugging / 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 PC). 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 computer 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, antivirus 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 on the basis 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 infected machine and unplugging / 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 PC).

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 9:22 am