Thursday, July 20, 2023

FantasyMW, a brazilian banking trojan

Update: Apparently this is a rebrand from an existing malware family called GoatRat and it was named as FantasyMW. More details at:

Sample seen from MalwareHunterTeam's tweet.

The sample is written in kotlin and under a Windows host OS. This is possible to guess because the strings hint to Windows paths. At the time of the analysis the domains were not resolving. It seems to be a new or under development banking trojan, as hinted by the path strings:


This is not the first ITW sample of this developer. The first ITW sample was seen on 2023-06-06 13:25:28 UTC and uses a different path for development: 


The path differs from the latest spotted sample. Since this is a brazilian malware, I chose to dub it as Casanossolar from the package name instead of FantasyMalware. 

This malware requests accessibility permissions and overlay permissions to perform its activities. A complete list of permissions requested:









The sample contains URLs pointing to a ping endpoint and an initialization URL. On initialization, the device information such as hwid, device model, manufacturer is sent to the C2. The CLIENT_ID hardcoded in each sample is sent on each ping attempt.



It currently targets only 6 applications, but all of them are bank applications from Brazil/Portugal. It calls PackageManager.getInstalledPackages to obtain the list of installed applications. Each targeted application has a separate class for each of them with shared methods. It applies overlays to steal credentials when the user tries to access their bank application.

Complete list of targeted applications as of 2023-07-20.

  • com.picpay

The first versions don't feature emulator checks on startup. However the latest samples contain emulator checks on startup and attempts to detect Android x86, Android Emulators, and XPosed among others:

  • goldfish

  • ranchu

  • google_sdk

  • Emulator

  • Android SDK built for x86

  • Genymotion

  • sdk_google

  • google_sdk

  • sdk

  • sdk_x86

  • vbox86p

  • emulator

It also makes use of RootBeer to verify if there is root available on the device:

One of the first samples contains an image presumably from the developer, referring to himself as "Sicko", mentioning that you are being hacked and a identifier to purchase his malware. Reverse image search returns nothing, so it seems to be handcrafted by the author.

In in one of the first versions seen in the wild, there is a Discord webhook URL and the Discord webhook module is also present in the code. Since the latest spotted samples exclude the Discord hooks, it points to the author relying only on their backend.

There are different builds of the same code with different icons, in an attempt to deceive users to install the application in their device or be trusted.

Overall, it looks like a family still in development. I will update this post with any updates and update the sample collection as well.


Virustotal Collection:












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