Trojan.Agent.Formbook monitors activity on the Firefox web browser in order to steal login details for the Facebook social media network.
Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.
A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:
Check for the latest database updates
First check if your F-Secure security program is using the latest updates, then try scanning the file again.
Submit a sample
After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.
Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.
Exclude a file from further scanning
If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.
Note: You need administrative rights to change the settings.
Note: Description is based on analysis of sample (SHA1) 524e1011c26b6bf7e23f5d107222397129f9893d.
In addition to stealing login details, Trojan.Agent.Formbook can also:
The trojan is spread as a specially-crafted document file attached to spam email messages. If the user opens the attached file, the trojan is launched.
Trojan.Agent.Formbook checks the computer for any common anti-debugging techniques or keywords, such as "VM", "Sandbox", ÃƒÂ¢Ã¢,Â¬Ã…""VMWare Users.exe", and "VMWare Service". If any are found, the trojan immediately exits.
This step is intended to make it harder for security researchers to analyze the malware.
The trojan adds the following registry key to the Windows registry so that it will automatically run whenever the computer is started:
Trojan.Agent.Formbook drops multiple script files with random extensions in a folder named CNE in the Temp folder, with most being decoys to camouflage its actual usable components. Examples of some of the files it drops are:
The trojan uses the following command to run the pwm-axa script file:
It then runs another script file, this one with a random name. As an example, the script file CDWDY is run next using the following argument:
This script launches a new thread and injects it into the explorer.exe process by using the following sequence of command prompts:
From there, the trojan can begin monitoring the Firefox browser for activity.
If the user opens Facebook's login page in the Firefox browser, Trojan.Agent.Formbook steals any data the user enters into the login form on the page. The stolen data is then forwarded to the trojan's C&C server.
The trojan attempts to connect to the following remote servers:
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