PetrWrap Ransomware

A new variant of what is believed to PetrWrap ransomware is leveraging a modified EternalBlue SMBv1 exploit (patched in MS017-010) which WannaCry used to self-propagate to local and remote networks.

Threat ID:: CC-1287
Category:: Ransomware
Threat Severity:: Medium
Threat Vector:: Exploit
Published:: 22 March 2017 12:00 AM

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Summary

A new variant of what is believed to PetrWrap ransomware is leveraging a modified EternalBlue SMBv1 exploit (patched in MS017-010) which WannaCry used to self-propagate to local and remote networks.

Affected platforms

The following platforms are known to be affected:

Microsoft Windows

All Windows versions

Threat details

Coverage of this threat is now found here Petya Self Propagating Ransomware CC-1492

Security researchers have identified a new ransomware called PetrWrap that is based on Petya, a ransomware family offered as a service (RaaS).

The authors of Petya created a number of mechanisms to prevent other attackers using their code without paying for the service. These obstacles have been mitigated by the authors of PetrWrap suggesting that they possess advanced technical capability.

PetrWrap is distributed after first penetrating a target network through unprotected RDP access. After gaining a foothold on the network, the ransomware uses PsExec to execute copies of itself on target machines.

Other publicly available tools such as Mimikatz are used in order to obtain the necessary account credentials for privilege escalation in order to traverse the target network.

After a successful attack, PetrWrap displays a ransom note directing the affected user to a payment website.

Remediation steps

Type	Step
	If your network becomes infected immediately report it to your AV provider for investigation and patching Ensure your AV software is kept updated with the very latest security definitions, to detect current and evolving strains of malware which leverages this vulnerability. Confirm with your AV provider that they have rolled out virus definitions which are supported by your organisation's operating systems to protect you from the spread of this malware (especially if your organisation is running out of support operating systems). Ensure your AV software is properly configured and automatically scans all files and file operations (including file reads, writes and re- SMB Vulnerability Remediation Apply the vulnerability remediation detailed here SMB EternalBlue and DoublePulsar Exploit (CC-1353) Ransomware Remediation 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 your network becomes infected immediately report it to your AV provider for investigation and patching
Ensure your AV software is kept updated with the very latest security definitions, to detect current and evolving strains of malware which leverages this vulnerability.
Confirm with your AV provider that they have rolled out virus definitions which are supported by your organisation's operating systems to protect you from the spread of this malware (especially if your organisation is running out of support operating systems).
Ensure your AV software is properly configured and automatically scans all files and file operations (including file reads, writes and re-

SMB Vulnerability Remediation

Apply the vulnerability remediation detailed here SMB EternalBlue and DoublePulsar Exploit (CC-1353)

Ransomware Remediation

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: 21 December 2021 12:40 pm