MnuBot banking trojan communicates via SQL server

Posted by   Martijn Grooten on   May 30, 2018

Researchers at IBM X-Force have discovered a new banking trojan, dubbed 'MnuBot', which is targeting Internet users in Brazil.

The trojan performs tasks common to banking malware, such as logging keystrokes, creating screenshots and overlaying the bank's website with an invisible form. What is most noticeable, though, is the use of a Microsoft SQL server for C&C communication.

It is common for malware authors to put a lot of effort into trying to evade detection both of the activities on the endpoint and of all network communication. The use of SQL server could just be another example of that. However, I agree with SANS's Johannes Ullrich who, speaking on his daily podcast, pointed out that simply using HTTPS would have sufficed to make the network traffic undetectable.

Moreover, the credentials required to access the SQL database are present in the malware itself: they are dynamically decrypted just before the connection to the database server is made, making them accessible to someone analysing the malware.

mnubot_wireshark.png

MnuBot's network communication in Wireshark clearly shows the SQL commands used. Source: IBM.

Brazil has long been a hotbed of cybercrime and there are many malware families that specifically target the country's Internet users. As IBM's Jonathan Lusky said in the blog post about the malware, the use of overlaying forms and the creation of new desktops are techniques seen in other Brazilian banking malware too.

Update: shortly after this blog post was published, Kaspersky Lab researcher Fabio Assolini, who has regularly spoken at VB conferences on cybercrime in his native Brazil, contacted us to say that he has seen this technique being used since 2014 and pointed out a 2015 McAfee blog post which describes an example of a similar technique.

twitter.png
fb.png
linkedin.png
hackernews.png
reddit.png

 

Latest posts:

The spam that is hardest to block is often the most damaging

We see a lot of spam in the VBSpam test lab, and we also see how well such emails are being blocked by email security products. Worryingly, it is often the emails with a malicious attachment or a phishing link that are most likely to be missed.

Throwback Thursday: We're all doomed

Mydoom turns 15 this month, and is still being seen in email attachments. This Throwback Thursday we look back to March 2004, when Gabor Szappanos tracked the rise of W32/Mydoom.

VB2019 call for papers - now open!

Have you analysed a new online threat? Do you know a new way to defend against such threats? Are you tasked with securing systems and fending off attacks? The call for papers for VB2019 is now open and we want to hear from you!

VB2018 paper: Unpacking the packed unpacker: reversing an Android anti-analysis library

Today, we publish a VB2018 paper by Google researcher Maddie Stone in which she looks at one of the most interesting anti-analysis native libraries in the Android ecosystem. We also release the recording of Maddie's presentation.

VB2018 paper: Draw me like one of your French APTs – expanding our descriptive palette for cyber threat actors

Today, we publish the VB2018 paper by Chronicle researcher Juan Andres Guerrero-Saade, who argues we should change the way we talk about APT actors.

We have placed cookies on your device in order to improve the functionality of this site, as outlined in our cookies policy. However, you may delete and block all cookies from this site and your use of the site will be unaffected. By continuing to browse this site, you are agreeing to Virus Bulletin's use of data as outlined in our privacy policy.