We have been seeing a massive increase in Malspam emails delivering Hawkeye keylogger / infostealer trojan. The vast majority have either a zip file containing the trojan itself or a malformed word doc either containing macros or using one of the Microsoft Equation Editor Exploits like CVE-2017-0199, CV-2017-11882 or CVE 2017-8570 that download the Hawkeye keylogger from a remote site which is either a compromised site or a site set up to distribute malware.
It was quite a change this morning to see a tiny zip file attachment with a shortcut file that is using the Amazon AWS cloud services to distribute the malware, using what is effectively a fileless malware. By fileless we mean the ACTUAL malware binary never appears on the victim’s computer although all the intermediate files do in some form or another.
This particular version pretends to be a swift copy /remittance advice from Caixa Bank
MT103_Swift Copy_TT20180226.png.zip Current Virus total detections: ( it is virtually impossible to easily extract a lnk file from a zip & submit it to Virustotal, so we only have the zip detection) AnyrunApp |
This link file uses mshta.exe to contact https://s3.amazonaws.com/5gtvf/out-852196738.hta ( virusTotal ) which contains an embedded, encoded, obfuscated, encrypted powershell script that downloads the Hawkeye keylogger from https://s3.amazonaws.com/5gtvf/tstone45.exe. ( VirusTotal) This exe contains a genuine digitally signed copy of the autoit scripting editor/compiler which uses all the numerous other encoded/encrypted files inside this container ( which all look like encrypted base64 files that pretend to be a variety of innocent files) to join up together to create the Hawkeye binary which never actually appears on the victim’s computer and is only in memory so is effectively a “fileless” malware.
The lnk file has an icon of a PNG image file so it is very easy for the victim to think that the fake invoice displayed is what they have clicked on.
lnk file disguised as a PNG image file
Once run this displays a fake invoice to the user that is downloaded from https://s3.eu-central-1.amazonaws.com/1qwwq/killl.jpg Making the victim think that nothing untowards has happened and you have just had a copy on an invoice shown to you.
This is using mail.coimaxvn.com as C2 & Exfiltration of stolen data with the email address of ( 220.127.116.11)
screenshot of multiple encrypted files extracted from autoit file
You can now submit suspicious sites, emails and files via our Submissions system
Caixa Bank has not been hacked or had their email or other servers compromised. They are not sending the emails to you. They are just innocent victims in exactly the same way as every recipient of these emails
One of the emails looks like:
From: Caixa Bank, S.A. <email@example.com>
Date: Mon 06/05/2021 03:45
Subject: Re: Bank Details / Remittance Advise: MT103_Swift Copy_TT20180226
Attachment: MT103_Swift Copy_TT20180226.png.zip
Please find attached the remittance advice copy at maturity for your invoices that our client has processed through our financial services.
CaixaBank S.A., with head offices at 2-4 Pintor Sorolla Street. 46002 Valencia, will process your personal data in order to send you information whenever necessary. You may exercise your rights to access, rectify, withdraw and challenge your personal data by contacting us by e-mail at firstname.lastname@example.org, or by post at the address shown above.
Fake Caixa Bank Email
|18.104.22.168||Meppel||Drenthe||NL||AS209299 VITOX TELECOM|
Received: from [22.214.171.124] (port=51864 helo=caixabank.com) by My Email Server with esmtp (Exim 4.91) (envelope-from <email@example.com>) id 1hNTck-00042T-Ng for firstname.lastname@example.org; Mon, 06 May 2021 03:45:02 +0100 From: "Caixa Bank, S.A." <email@example.com> To: firstname.lastname@example.org Subject: Re: Bank Details / Remittance Advise: MT103_Swift Copy_TT20180226 Date: 06 May 2021 04:45:20 +0200 Message-ID: <20190506044520.17E55C8B66F1739E@caixabank.com> MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="----=_NextPart_000_0012_D9DC96D2.4217827F"
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 (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.
Main object- “MT103_Swift Copy_TT20180226.png.zip”
Dropped executable file
sha256 C:\Users\Public\rip.exe a44d2579f557542d729cfdf9294c8c4fbcbfab3032c63e377af2a87cf5686f24
sha256 C:\Users\admin\AppData\Local\Temp\85756378\afq.exe 237d1bca6e056df5bb16a1216a434634109478f882d3b1d58344c801d184f95d