DoppelPaymer Ransomware

First observed in April 2019, DoppelPaymer is a ransomware tool based on the older BitPaymer malware.

Threat ID:: CC-3153
Category:: Ransomware
Threat Severity:: Low
Threat Vector:
Published:: 18 July 2019 12:00 AM

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

Summary

First observed in April 2019, DoppelPaymer is a ransomware tool based on the older BitPaymer malware.

Affected platforms

The following platforms are known to be affected:

Microsoft Windows

Microsoft Windows - All versions

Threat details

At the time of publication, it is unclear how DoppelPaymer is distributed. However, it's similarities with BitPaymer suggest it may employ the same delivery vectors, including over insecure Remote Desktop Protocol connections or via spam campaigns.

Once installed, DoppelPaymer will check for a specific command line argument, terminating itself if this is not present, in an attempt to prevent automated analysis. It will then terminate anti-virus, backup, database and email processes using the open-source ProcessHacker tool. DoppelPaymer will encrypt all local non-system files using an AES-256 algorithm, the key for which is then itself encrypted using a hard-coded RSA-4096 key.

DoppelPaymer can also attempt to enumerate the local network by parsing the affected system's Address Resolution Protocol table to gather connected host IP addresses.

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: 14 February 2020 2:49 pm