Following on from the earlier malware campaign using Mailchimp, we are seeing a bit of a change in the emails, the downloaded files & the eventual payload. They are still eventually delivering what looks like Gootkit banking trojan.
This next email with the subject of Invoice for Company: 22/02/2018 coming from Infinity Cottage <email@example.com>; on behalf of; Infinity Cottage <firstname.lastname@example.org> with 2 different links in the email body. The first link downloads a zip attachment which contains a .js file that downloads a .scr file ( screensaver files run as a .exe on windows computers ). The second link downloads a macro enabled word doc that also downloads the same .scr file.
About 1 month ago we saw a malware campaign using Mailchimp to distribute Gootkit banking trojan. Today’s campaign has changed slightly and although the initial emails are coming via the Mailchimp system, the malware downloaders and payloads are coming from other sites which are probably/almost certainly compromised.
They use email addresses and subjects that will entice a user to read the email and open the attachment. A very high proportion are being targeted at small and medium size businesses, with the hope of getting a better response than they do from consumers.
The first link in the email is to https://vnntravel.com/company invoice 2-22-2018.zip ( which is also behind cloudflare )
The second link is to https://menvisinhbifina.com/22.02.18.doc
Both of these malware files download from http://fsamch.com/fictions.scr VirusTotal |Anyrun Beta | This is somewhat larger than the earlier version we saw but still appears to be gootkit banking trojan from the indicators in the sandbox reports
One of the emails looks like:
From: Infinity Cottage <email@example.com>; on behalf of; Infinity Cottage <firstname.lastname@example.org>
Date: Thu 22/02/2018 11:13
Subject:Invoice for Company: 22/02/2018
Invoice for WildAid – Home
Please view/download company invoice.
Or you can find your invoice here.
Copyright © 2018 Infinity Cottage, All rights reserved.
Our mailing address is:
PO Box 1367
Sale, Victoria 3853
Add us to your address book
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|18.104.22.168||mail75.sea61.rsgsv.net||Atlanta||Georgia||US||AS14782 The Rocket Science Group, LLC|
Received: from [22.214.171.124] (port=50156 helo=mail75.sea61.rsgsv.net)
by knight.knighthosting.co.uk with esmtp (Exim 4.89_1)
for email@example.com; Thu, 22 Feb 2018 11:12:41 +0000
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; s=k1; d=mail75.sea61.rsgsv.net;
Received: from (127.0.0.1) by mail75.sea61.rsgsv.net id hhqiqk2ddl4l for <firstname.lastname@example.org>; Thu, 22 Feb 2018 11:12:30 +0000 (envelope-from <email@example.com>)
From: =?utf-8?Q?Infinity=20Cottage?= <firstname.lastname@example.org>
Reply-To: =?utf-8?Q?Infinity=20Cottage?= <email@example.com>
To: =?utf-8?Q?WildAid=20=2D=20Home?= <firstname.lastname@example.org>
Date: Thu, 22 Feb 2018 11:12:30 +0000
X-Mailer: MailChimp Mailer – **CID2f31f7b73ba4fdc96049**
X-Report-Abuse: Please report abuse for this campaign here: http://www.mailchimp.com/abuse/abuse.phtml?u=0cec3aca2a26beb86125d769a&id=2f31f7b73b&e=a4fdc96049
List-ID: 0cec3aca2a26beb86125d769amc list <0cec3aca2a26beb86125d769a.834045.list-id.mcsv.net>
List-Unsubscribe: <https://infinitycottage.us2.list-manage.com/unsubscribe?u=0cec3aca2a26beb86125d769a&id=fd6ccf95d8&e=a4fdc96049&c=2f31f7b73b>, <mailto:email@example.com?subject=unsubscribe>
Sender: “Infinity Cottage” <firstname.lastname@example.org>
Content-Type: multipart/alternative; boundary=”_———-=_MCPart_170323307″
This is a multi-part message in MIME format
These malicious attachments normally have a password stealing component, with the aim of stealing your bank, PayPal or other financial details along with your email or FTP ( web space) log in credentials. Many of them are also designed to specifically steal your Facebook and other social network log in details. A very high proportion are Ransomware versions that encrypt your files and demand money ( about £350/$400) to recover the files.All the alleged senders, amounts, reference numbers, Bank codes, companies, names of employees, employee positions, email addresses and phone numbers mentioned in the emails are all random. Some of these companies will exist and some won’t. Don’t try to respond by phone or email, all you will do is end up with an innocent person or company who have had their details spoofed and picked at random from a long list that the bad guys have previously found. The bad guys choose companies, Government departments and organisations with subjects that are designed to entice you or alarm you into blindly opening the attachment or clicking the link in the email to see what is happening.
Please read our How to protect yourselves page for simple, sensible advice on how to avoid being infected by this sort of socially engineered malware.
This is another one of the files that unless you have “show known file extensions enabled“, can easily be mistaken for a genuine DOC / PDF / JPG or other common file instead of the .EXE / .JS file it really is, so making it much more likely for you to accidentally open it and be infected.
Be very careful with email attachments. All of these emails use Social engineering tricks to persuade you to open the attachments that come with the email. Whether it is a message saying “look at this picture of me I took last night” and it appears to come from a friend or is more targeted at somebody who regularly is likely to receive PDF attachments or Word .doc attachments or any other common file that you use every day.
The basic rule is NEVER open any attachment to an email, unless you are expecting it. Now that is very easy to say but quite hard to put into practice, because we all get emails with files attached to them. Our friends and family love to send us pictures of them doing silly things, or even cute pictures of the children or pets.
Never just blindly click on the file in your email program. Always save the file to your downloads folder, so you can check it first. Many malicious files that are attached to emails will have a faked extension. That is the 3 letters at the end of the file name. Unfortunately windows by default hides the file extensions so you need to Set your folder options to “show known file types. Then when you unzip the zip file that is supposed to contain the pictures of “Sally’s dog catching a ball” or a report in word document format that work has supposedly sent you to finish working on at the weekend, or an invoice or order confirmation from some company, you can easily see if it is a picture or document & not a malicious program.
If you see JS or .EXE or .COM or .PIF or .SCR or .HTA .vbs, .wsf , .jse .jar at the end of the file name DO NOT click on it or try to open it, it will infect you.
While the malicious program is inside the zip file, it cannot harm you or automatically run. When it is just sitting unzipped in your downloads folder it won’t infect you, provided you don’t click it to run it. Just delete the zip and any extracted file and everything will be OK. You can always run a scan with your antivirus to be sure. There are some zip files that can be configured by the bad guys to automatically run the malware file when you double click the zip to extract the file. If you right click any suspicious zip file received, and select extract here or extract to folder ( after saving the zip to a folder on the computer) that risk is virtually eliminated. Never attempt to open a zip directly from your email, that is a guaranteed way to get infected. The best way is to just delete the unexpected zip and not risk any infection.