Emotet

You may have heard of the Trojan Emotet before, first appearing back in 2014 stealing banking information, it has since evolved into a multi-faceted threat that targets everyone. It uses social engineering through emails to attempt to convince the user to open a Microsoft Word document and run its malicious macros. Even more worrisome is that once they have infected a target, they attempt to take over the victims Microsoft outlook desktop application. If successful Emotet will go through all sent emails and contacts, before sending out a new wave of spam emails. Only this time it will be from a trusted email. A campaign from Emotet over the Christmas season reads like a friend sending a friendly season greeting.

Dear <name>,

You make the stars shine brighter and the winter days warmer just by being in my life. Merry Christmas to my favorite person in the world.

Merry Christmas and a wonderful New Year!

Greeting Card is attached

A lovely thing about Christmas is that it’s compulsory, like a thunderstorm, and we all go through it together. Garrison Keillor

While not limited to invoices or Christmas cards, these emails attempt to get the user to click the download link and then to open the document. In the email mentioned above the target may be fooled into thinking that the attached greeting card is legitimate.  The document actually contains a malicious macro, an embedded script. While macros were initially designed to help automate keystrokes and mouse movements, they were quickly abused by nefarious virus creators. The infection cannot run on its own as Microsoft has automatically disabled macros more than a decade ago to help stop these malicious scripts. Instead, Emotet uses a few techniques to get the user to re-enable macros. Examples can be seen below.



The picture urges the user to click the Enable Content button, implying that they cannot view the Word document until they do so. You may have already noticed that the bar itself says that Macros have been disabled and the enable content button will in fact allow them. The moment that Enable content is click the macros will start and in seconds you will be infected, even worse in most cases you will have no indication from this point forward that anything is wrong. In one test case we briefly had a command window appear:



This window lasted less than two seconds before disappearing. This attack vector is not unique to Emotet though. In fact, it has been used by a number of ransomware attacks in the past. If you ever see a document you didn’t expect to receive, you should always be extremely cautious with it and you should never enable macros without a very good reason.

How it works

Emotet is an evolving malware that has been known to primary spread itself through the use of email spam campaigns.  Emotet itself does not attempt to do much harm, instead it opens the door for other malware who pay the doorman on the way in. It achieves this by using what is known as a Command and control server (C&C), Emotet will request instructions from its control server who will issue a new command. This command could be anything from grab this malware sample and run it to tell me what passwords are stored in the user’s browser. Emotet can also receive updates and new capabilities in this way as well, showing that if Emotet has infected your computer or network it should be removed as quickly as possible.

Emotet doesn’t stop at the first computer infected though, once it’s on a network it will attempt to get to all computers it’s connected to through a brute-force attack. Unless strong passwords are enforced on machines and all known vulnerabilities are patched, a single installation of Emotet can cause every computer in the network to become infected. Emotet is often updated with new exploits as they are found, meaning that while it may not be successful at first it will keep trying until it finds something that does work.

Code

We won’t go into too much depth on the actual code itself, but a brief step-by-step walkthrough can be useful to get a better understanding on how this malware works.

1. In the Word document there is a VBA script that is obfuscated so that you cannot read it at a glance, all this code does is launch a command shell which then launches PowerShell, a more powerful version of the Windows command shell.

2. Using PowerShell, the script attempts to download the core Emotet payload from a large variety of distribution websites.

3. The randomly named payload will then reach out to the main server and request a command. The command will change based on the campaign that is running, it could go grab new malware or it could attempt to use your own email address as a way to spread itself.

Who is affected

Many people assume that they will not be targets of malware campaigns, Emotet though targets everyone equally, it has the simple goal of getting on every machine it can and then getting paid to let other, more targeted malware come in behind it. If your email address has ever been sold, disclosed in a breach, or was on a friend’s email list when they got infected it’s possible you will receive a malicious email from them.

Indicators of infection

The main location for the executable is in C:\Users\<name>\AppData\Local\ and then whatever new name Emotet decides to use. One we have seen often is archivessymbol but this will change. If you see something in this folder you don’t know about, its important to run a scan.

Versions of Emotet can also drop files onto your computer in C:\Users\Public or C:\Users\<username>:

These files generally have 5-6 randomly generated numbers in the file name, followed by .exe. These are not actually executable files, but HTML documents that are used to generate revenue for the Blackhat’s by simulating clicks on web advertisements.

What you can do


If you or someone you know is infected with the Emotet malware download SUPERAntiSpyware Professional right now and get a 14 day free trial, no credit card required.  SUPERAntiSpyware is easy to install and will detect and remove Emotet from any Windows computer. If you are a Computer Technician, you may like to try our SUPERAntiSpyware Tech Edition solution, now free for the next 30 days. Use Tech01 as the Tech ID.  Click here: https://www.superantispyware.com/technician-download.html

Emotet has also been known to exploit a vulnerability in Windows called EternalBlue. Microsoft has issued a patch for this, and applying this patch can help protect you from Emotet as well as other malware who utilize this exploit.

HOW TO REMOVE EMOTET

  1. Restart the infected computer in safe mode without networking
  2. Search through the Indicators of infection and investigate any files/folders you do not recognize. You can run the file through SUPERAntiSpyware or online through VirusTotal.com to confirm that it is malware.
  3. Delete files and folders that have been confirmed as malware.
  4. Repeat steps 1-3 on all other machines in the network.
  5. Restore all infected computers to normal mode only after confirming the infection is removed.

Watch out for fake Office 365 phishing emails!

that claims to be Microsoft attempting to inform users their Office account email storage space is almost full and to prevent incoming/Outgoing mail from getting bounced back, to click the supplied link to add an additional 10 gigs of free and mandatory storage. This of course is an obvious scam to phish your password as the link takes you to a fake Office 365 login screen.

Example of the spam. Beyond the obvious sketchy character of the email, hovering over the links within the email with your mouse pointer clearly shows it takes you to a different website and not a Microsoft website.

We here at SUPERAntiSpyware recommend you simply delete this email, and do not click any links within the email. If you have been scammed by this email, immediately change your Office 365 account password and consider looking into changing your spam settings to avoid future spam emails such as these. Remember, if you do not recognize the sender address, do not open the email, and also if you do open an email always hover your mouse pointer over the emails links to see where they’re trying to take you.

Watch out for fake “Microsoft account Verify your email address” spam!

Verify Your Email Address

We at SUPERAntiSpyware have noticed in uptick in spam that claims to be associated with verifying your email address to set up a Microsoft Account.

Fake Microsoft account verification email

We recommend you immediately delete this email, do not click the “Verify Your email address button” it will redirect you to a known phishing site to try to steal your account information. You can tell the button is fake by simply hovering your mouse over the button and taking a look at the URL, clearly non-Microsoft related.

Clicking this button does not verify your account, it brings you to a phishing website that will lure you into giving up your account information!

If you have been scammed by this email, immediately change your Microsoft account password and consider looking into changing your spam settings to avoid future spam emails such as these. Remember, if you do not recognize the sender address, do not open the email!