PcClient.VK, a variant of PcClient, is a Trojan. PcClient.VK attempts to hide processes, files, registry data and network connections and allows the attacker to perform arbitrary actions on the infected machine. PcClient.VK has a rootkit functionality and steals sensitive information from an infected computer.
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.
PcClient.VK is seen in the wild as the payload file installed on a host machine by a specially crafted Microsoft PowerPoint file that contains exploit code.
Once execution of PcClient.VK been initiated, its executable component will drop the following hard-coded files in the Windows System directory:
Note: the file size of Ybrcuugm.d1l might vary due to garbage code appended at the end of the file.
It will also drop the following driver that will communicate with the dll files in order to hide the malware's processes, registry entries and files:
Moreover it also hides some network traffic that the PcClient.VK uses.
It modifies the following known registry entry as its autostart technique:
Data before:
Data after:
In order for the system to work normally, Ybrcuugm.dll will execute its malicious routine and then pass the correct parameter to the original dmserver.dll.
It also adds the following autostart registry entry for the driver:
Part of its payload is that is logs all the keystrokes made by the user and saves it to the following file:
It then sends this file to a remote hacker.
Another part of the payload is that it has a backdoor component. The backdoor routine is injected into svchost.exe, which is capable doing the following:
This malware connects to the following site: