A rather strong wave of old malware is resurfacing the Web. In this article we will analyze the Bayrob Trojan (Win32/Bayrob, Trojan.Bayrob!gen8, Trojan.Bayrob) which hasn’t been active for at least 9 years. The threat has been updated and set on the loose. Bayrob’s malicious code is now more precise and is up-to-date with recent malware.
|Type||Trojan, Infostealer, Backdoor|
|Short Description||The Trojan hasn’t been active for over 9 years, but has been just caught active by security researchers.|
|Symptoms||An error message is displayed “This application is not compatible with the recent version of Windows you’re running…”.|
|Distribution Method||Spam email attachments.|
|Detection Tool|| See If Your System Has Been Affected by malware |
Malware Removal Tool
|User Experience||Join Our Forum to Discuss Bayrob Trojan.|
A Look into Bayrob’s Latest Infections
Bayrob December 2015
Bayrob hasn’t been active since 2007, at least not in aggressive and widely-spread campaigns. However, the threat re-emerged last winter, in December, when it was spotted again by security researchers. Bayrob was spreading via malicious attachments in emails trying to impersonate Amazon.
Bayrob classifies as an infostealer and a backdoor type of Trojan. During December’s attacks, the Trojan was set to steal and send to a command and control server the following details from a victim’s machine:
- OS version
- Computer Name
- PC’s IP Address
- Information about the OS and system settings
- MAC address
- List of running services
Bayrob was spotted active again about 2 weeks ago. Apparently, the Trojan has new versions and its code has been modified to evade reverse engineering and detection.
Bayrob Version 2016
What hasn’t been changed in Bayrob’s code? In both its past and current attacks, the Trojan is designed to set up a proxy server to steal sensitive information from victim machines. What’s new in Bayrob is its improved capability to avoid detection and clone itself to launch multiple processes. Each of the processes (services) has its own malicious task to handle.
Fortinet researchers have discovered that Bayrob’s original sample:
drops one copy of itself, runs the first copy, and exits. The name of the first copy is a fixed prefix (“ulms” in the sample we analyzed), appended with a randomly generated string. The original process also displays a fake error message to hide its actual malicious behavior. Below [see picture] shows how it achieves this and the actual message. The first copy then drops another copy of itself. It also creates and starts a service, as shown below. The service runs major tasks such as C&C communication.
Bayrob is also capable of differentiating its running stage in the multiple processes/services by file names. The Trojan also drops identifiers to recognize its lifecycle stage.
Its latest versions are also set to perform code obfuscation, use dead code and apply encryption. Bayrob is now able to encrypt data while harvesting and exfiltrating data from the victim’s computer. The encryption usually gets in the way of security researchers’ analysis and anti-malware software’s detection.
Learn More about Code Obfuscation
Bayrob’s communications with its command & control server are also encrypted, and it also uses a custom protocol over TCP/IP.
Finally, here is a list of Bayrob’s detection names, via VirusTotal:
- Trojan.Bayrob.1 [Dr.Web]
- a variant of Win32/Bayrob.AA [ESET-NOD32]
- W32/Bayrob.T!tr [Fortinet]
- Trojan.Win32.Bayrob [Ikarus]
- TrojanSpy:Win32/Nivdort.AF [Microsoft]
- Mal/Bayrob-B [Sophos]
- TROJ_BAYROB.SM0 [TrendMicro-HouseCall]
- Gen:Variant.Diley.1 [Bitdefender]
- Win32/Cryptor [AVG]
Remove Bayrob Trojan and Protect Your System
As with other Trojans, the most secure way to prevent an infection is via having an active anti-malware protection on the system. If you have been affected, refer to the removal steps below to try and remove the Trojan completely, automatically or manually.
- Guide 1: How to Remove Bayrob Trojan from Windows.
- Guide 2: Get rid of Bayrob Trojan from Mac OS X.
- Guide 3: Remove Bayrob Trojan from Google Chrome.
- Guide 4: Erase Bayrob Trojan from Mozilla Firefox.
- Guide 5: Uninstall Bayrob Trojan from Microsoft Edge.
- Guide 6: Remove Bayrob Trojan from Safari.
- Guide 7: Eliminate Bayrob Trojan from Internet Explorer.
How to Remove Bayrob Trojan from Windows.
Step 1: Boot Your PC In Safe Mode to isolate and remove Bayrob Trojan
Step 2: Uninstall Bayrob Trojan and related software from Windows
Here is a method in few easy steps that should be able to uninstall most programs. No matter if you are using Windows 10, 8, 7, Vista or XP, those steps will get the job done. Dragging the program or its folder to the recycle bin can be a very bad decision. If you do that, bits and pieces of the program are left behind, and that can lead to unstable work of your PC, errors with the file type associations and other unpleasant activities. The proper way to get a program off your computer is to Uninstall it.
Step 3: Clean any registries, created by Bayrob Trojan on your computer.
The usually targeted registries of Windows machines are the following:
You can access them by opening the Windows registry editor and deleting any values, created by Bayrob Trojan there. This can happen by following the steps underneath:
Get rid of Bayrob Trojan from Mac OS X.
Step 1: Uninstall Bayrob Trojan and remove related files and objects
1. Hit the ⇧+⌘+U keys to open Utilities. Another way is to click on “Go” and then click “Utilities”, like the image below shows:
- Go to Finder.
- In the search bar type the name of the app that you want to remove.
- Above the search bar change the two drop down menus to “System Files” and “Are Included” so that you can see all of the files associated with the application you want to remove. Bear in mind that some of the files may not be related to the app so be very careful which files you delete.
- If all of the files are related, hold the ⌘+A buttons to select them and then drive them to “Trash”.
In case you cannot remove Bayrob Trojan via Step 1 above:
In case you cannot find the virus files and objects in your Applications or other places we have shown above, you can manually look for them in the Libraries of your Mac. But before doing this, please read the disclaimer below:
You can repeat the same procedure with the following other Library directories:
Tip: ~ is there on purpose, because it leads to more LaunchAgents.
Step 2: Scan for and remove malware from your Mac
When you are facing problems on your Mac as a result of unwanted scripts, programs and malware, the recommended way of eliminating the threat is by using an anti-malware program. Combo Cleaner offers advanced security features along with other modules that will improve your Mac’s security and protect it in the future.
Remove Bayrob Trojan from Google Chrome.
Step 1: Start Google Chrome and open the drop menu
Step 2: Move the cursor over "Tools" and then from the extended menu choose "Extensions"
Step 3: From the opened "Extensions" menu locate the unwanted extension and click on its "Remove" button.
Step 4: After the extension is removed, restart Google Chrome by closing it from the red "X" button at the top right corner and start it again.
Erase Bayrob Trojan from Mozilla Firefox.
Step 1: Start Mozilla Firefox. Open the menu window
Step 2: Select the "Add-ons" icon from the menu.
Step 3: Select the unwanted extension and click "Remove"
Step 4: After the extension is removed, restart Mozilla Firefox by closing it from the red "X" button at the top right corner and start it again.
Uninstall Bayrob Trojan from Microsoft Edge.
Step 1: Start Edge browser.
Step 2: Open the drop menu by clicking on the icon at the top right corner.
Step 3: From the drop menu select "Extensions".
Step 4: Choose the suspected malicious extension you want to remove and then click on the gear icon.
Step 5: Remove the malicious extension by scrolling down and then clicking on Uninstall.
Remove Bayrob Trojan from Safari.
Step 1: Start the Safari app.
Step 2: After hovering your mouse cursor to the top of the screen, click on the Safari text to open its drop down menu.
Step 3: From the menu, click on "Preferences".
Step 4: After that, select the 'Extensions' Tab.
Step 5: Click once on the extension you want to remove.
Step 6: Click 'Uninstall'.
A pop-up window will appear asking for confirmation to uninstall the extension. Select 'Uninstall' again, and the Bayrob Trojan will be removed.
Eliminate Bayrob Trojan from Internet Explorer.
Step 1: Start Internet Explorer.
Step 2: Click on the gear icon labeled 'Tools' to open the drop menu and select 'Manage Add-ons'
Step 3: In the 'Manage Add-ons' window.
Step 4: Select the extension you want to remove and then click 'Disable'. A pop-up window will appear to inform you that you are about to disable the selected extension, and some more add-ons might be disabled as well. Leave all the boxes checked, and click 'Disable'.
Step 5: After the unwanted extension has been removed, restart Internet Explorer by closing it from the red 'X' button located at the top right corner and start it again.