Classification

Category :

Malware

Type :

Trojan

Aliases :

Hooker, Trojan.PSW.Hooker

Summary

IMPORTANT NOTE: If you have been affected by this trojan, change your Windows domain and RAS password immediately.

Hooker is a password and data stealing trojan. Being run it installs itself as KERN32.EXE (name may differ in different versions) into \Windows\System\ directory and modifies RunOnce key in the Registry to be run during next Windows session. When activated next time the trojan renews the RunOnce key, so it becomes active during all Windows sessions.

Removal

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.

Technical Details

After initial installation the trojan drops a keylogging DLL from inside its body (as HKSDLL.DLL, but the name can be different in different versions) and registers itself as a service process. This way its task is not visible in Task Manager.

The trojan monitors keyboard commands, captures logins and passwords for RAS (Remote Access Server), gets information about a network (IPs, passwords, scripts) where an infected computer is connected to and sends all this info to an email address that is stored in encrypted format in the trojan's body. The trojan uses an anonymous mail server to send emails, the name of the server is also stored in the trojan's body in encrypted form.

The trojan is installed on an infected system for a limited time. After its time limit expires, the trojan deletes itself from a system.