SoFunction
Updated on 2025-04-08

Simple analysis of viruses


Main behavior:

1. Release the file:

C:\Windows\System32\
671,744 bytes
C:\Windows\Tasks\
346 bytes

2. Add startup item:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run

The key name is: Yahoo Messengger, pointing to.

3. Modify the registry and start with Explorer:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
Shell = "  "

4. Disable the registry and task manager:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System
DisableTaskMgr = 0x00000001 
DisableRegistryTools = 0x00000001

5. Connect to the network and download messy things (unimplemented):

hxxp://nhatquanglan2./ 
hxxp://nhatquanglan2./ 
hxxp:///nhattruongquang/ 
hxxp:///nhattruongquang/

6. Add a planned task:


C:\Windows\Tasks\

346 bytes ~~

Solution:

1. Download Sreng. Disconnect the network afterwards.


2. Open Sreng and it will prompt


HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon

The item is maliciously modified and will be automatically repaired after clicking OK.

3. Delete Yahoo Messengger and point to ((Detailed steps: Open SREng - Start Project - Registration)).

4. Restart the computer and delete the file:

C:\Windows\System32\
C:\Windows\Tasks\