StorageCrypt Ransomware

StorageCrypt is a new family of ransomware that targets network-attached storage (NAS) devices using SambaCry (CVE-2017-7494). SambaCry allows remote attackers to execute arbitrary code on targeted systems by uploading a shared library to a writable network share, and then causing the server to load that library.

Threat ID:: CC-1858
Category:
Threat Severity:: Medium
Threat Vector:
Published:: 14 December 2017 12:00 AM

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

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Summary

Threat details

StorageCrypt uses SambaCry in the same ways as ShellBind. Both download a file called sambacry to the /tmp folder as apaceha, and then run it.

It encrypts and renames the files and appends the .locked extension to them before dropping a ransom note containing the ransom amount, the attackers’ Bitcoin address, and email address JeanRenoAParis@protonmail[.]com.

Remediation steps

Type	Step
	Administrators are encouraged to upgrade to a version of Samba that is not affected by the vulnerability. 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

Administrators are encouraged to upgrade to a version of Samba that is not affected by the vulnerability.

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.

CVE Vulnerabilities

CVE-2017-7494

Last edited: 11 January 2022 9:24 am