The gangs spreading malware via the “cannot deliver your parcel notifications” or “check where your parcel is” spoofing FedEx, DHL, UPS, USPS etc. have changed delivery method.
The emails are still very similar to the ones we are used to seeing with this sort of subject line.
- USPS issue #06914074: unable to delivery parcel
- Parcel #006514814 shipment problem, please review
- USPS parcel #3150281 delivery problem
- Courier was not able to deliver your parcel (ID006976677, USPS)
- Parcel 05836911 delivery notification, USPS
- Delivery Status Notification
Some of them, especially spoofing FedEx have a fake PGP public key block embedded in the body, trying to convince you that it is genuine. Almost all of these emails come from random senders. Some don’t even mention the delivery service in the sender field.
What has changed is the attachment to the emails that contains the malware. These now contain a HTML attachment that when opened displays a webpage on your computer that pretends to be a Microsoft Word online website and you need to download the MSOffice365 Webview Plugin update, with a blurry image of scrambled writing in the background with this message prominantly displayed “This document cannot be read in your browser. Download and install latest plugin version:”
This is where it starts to get interesting The link goes to a base 64 encoded package that is part of the webpage code. using data:application/zip;base64. Internet Explorer will not allow the opening of such data files on your computer & does nothing. But Both Firefox & Chrome will allow you to “download” the zip file & then infect yourself.
From here on the infection chain stays as it has been previously. Open zip file, extract .js file. That connects to 1 of 4 remote URLs which gives you a second .js file that in turn contains another 4 urls that actually link to the malware. Sometimes all the urls ( websites) are the same as the original js file, sometimes a mixture of those and new ones.
All of this has been previously described in THIS post from Mid April 2017 (https://myonlinesecurity.co.uk/changes-to-fake-usps-delivery-messages-delivering-malware/). Which shows the obfuscated / encoded nature of the files and how to decode/de-obfuscate them easily. At that time they linked to a remote website using the fake MSOffice365 scam. These malware gangs use a mix and match of different techniques to try to stay one step ahead of researchers and antivirus companies and gain more victims
Infection Chain From 31 May 2017:
- FedEx-Delivery-Details-ID-8AXP4QH0.doc.html attachment ( VirusTotal) ( Payload Security)
- Install-MSOffice365-WebView-Plugin-Update-0.165.11a.zip extracts to Install-MSOffice365-WebView-Plugin-Update-0.165.11a.exe.js ( VirusTotal) ( Payload Security)
- Counter.js ( VirusTotal) which downloads 2 files pretending to be png ( image files that are renamed .exe files) 1.exe currently Cerber Ransomware ( VirusTotal ) ( Payload Security ) 2.exe currently Kovter ( VirusTotal) (Payload Security )
The 4 sites embed in the original webview plugin.js are
Where you get counter.js from this
That then when decrypted gives these 4 sites
Where <sitename)/counter/?1 gives the Cerber ransomware and <sitename)/counter/?2 gives Kovter
As previously described, the js files try to contact the sites in order they are listed. It then tries each combination of <sitename>counter/?xxxxxxxxxxxxxxxxxx and if any site fails to respond, then moves to next site in the list and continues to do that until the counter.js & the actual malware files are downloaded and run on the victim’s computer
One of the emails looks like:
Date: Wed 31/05/2017 14:09
Subject: Delivery Status Notification
Please review your parcel delivery label in the attachment!
—–BEGIN PGP PUBLIC KEY BLOCK—–
—–END PGP PUBLIC KEY BLOCK—–
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.
Previous campaigns over the last few weeks have delivered numerous different download sites and malware versions. There are frequently 5 or 6 and even up to 150 download locations on some days, sometimes delivering the exactly same malware from all locations and sometimes slightly different malware versions. All the malwares update at frequent intervals during the day, sometimes as quickly as every hour, so you might ( almost certainly will ) get a different version of these nasty Ransomware or Banking password stealer Trojans.
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 (https://en.wikipedia.org/wiki/Social_engineering_(security)) 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.