W2KM_URSNIF.BYY Trojan Downloader Email Campaign

A recent email malware campaign is delivering a trojan downloader via a malicious attachment.

Threat ID:: CC-1305
Category:: Trojan
Threat Severity:: Medium
Threat Vector:: Email spam
Published:: 7 April 2017 12:00 AM

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

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Summary

A recent email malware campaign is delivering a trojan downloader via a malicious attachment.

Affected platforms

The following platforms are known to be affected:

Microsoft Windows

Microsoft Windows - all versions

Threat details

The attachment is a password protected macro enabled Word document which delivers the trojan downloader named :

W2KM_URSNIF.BYY (TrendMicro)
TrojanDownloader:O97M/Donoff (Microsoft)
Trojan-Downloader.MSWord.Agent.ahj (Kaspersky)

When a computer becomes infected with the trojan downloader it installs other malware on the user's PC.

The subject line of the message includes the recipient's name.
The message within the body of the email uses social engineering techniques to encourage the user to open the attachment and appears in the following format:

Good day to you, [recipient’s name]!

I am disturbing you for a very critical occasion. Allhough we are not familiar, but I have large ammount of information about you. The matter is that, most probably by mistake, the information of your account has been sent to me.
For instance, your address is:
[recipient’s postal address]

I am a lawful citizen, so I decided to private data may have been hacked. I pinned the file - Curtis.dot that was sent to me, that you could view what data has become accessible for deceivers. File password is - 9013

Best wishes,
[Changing Name]

Remediation steps

Type	Step
	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. Strong password policies are in place and password reuse is discouraged. Network, proxy and firewall logs should be monitored for suspicious activity.

Type

Step

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.
Strong password policies are in place and password reuse is discouraged.
Network, proxy and firewall logs should be monitored for suspicious activity.

Last edited: 17 February 2020 11:41 am