Annabelle Ransomware

A new ransomware tool that uses several advanced features has been observed. Known as Annabelle, it is believed to have been created to demonstrate its author's technical capabilities.

Threat ID:: CC-2104
Category:: Ransomware
Threat Severity:: Low
Threat Vector:: Email spam, Download
Published:: 8 March 2018 12:00 AM

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

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Summary

A new ransomware tool that uses several advanced features has been observed. Known as Annabelle, it is believed to have been created to demonstrate its author's technical capabilities.

Affected platforms

The following platforms are known to be affected:

Microsoft Windows

Microsoft Windows - All versions

Threat details

Annabelle is delivered via several different methods including free software downloads, spam email and malicious websites. When first run it will configure itself to start when the user logs in before terminating a number of programs. Annabelle then configures Image File Execution registry entries to disable the same set of programs from running. Attached USB drives are infected using autorun.inf files.

A static key is used for encryption, with encrypted files being appended with the extension .ANNABELLE. Once the encryption process is completed, the master boot record of the device is replaced, resulting in the affected device displaying a screen thanking several people when rebooted.

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. 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.
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: 17 February 2020 12:36 pm