Follow:

You have been re-routed to the Worm:Win32/Roopirs.A write up because Worm%3aWin32%2fRoopirs.A has been renamed to Worm:Win32/Roopirs.A
 

Worm:Win32/Roopirs.A


Worm:Win32/Roopirs.A is a worm that copies itself to mapped network drives and assumes the icon of a Windows folder to increase its chance of user execution.


What to do now

To detect and remove this threat and other malicious software that may be installed in your computer, run a full-system scan with an up-to-date antivirus product such as the following:
 
 
For more information on antivirus software, see http://www.microsoft.com/windows/antivirus-partners/.
Recovering from recurring infections on a network
The following additional steps may need to be taken to completely remove this threat from an infected network, and to stop infections from recurring from this and other similar types of network-spreading malware:
 
  1. Ensure that an antivirus product is installed on ALL computers connected to the network that can access or host shares.
  2. Ensure that all available network shares are scanned with an up-to-date antivirus product.
  3. Restrict permissions as appropriate for network shares on your network. For more information on simple access control, please see: http://technet.microsoft.com/library/bb456977.aspx.
  4. Remove any unnecessary network shares or mapped drives.
 
Note: Additionally it may be necessary to temporarily change the permission on network shares to read-only until the disinfection process is complete.

Threat behavior

Worm:Win32/Roopirs.A is a worm that copies itself to mapped network drives and assumes the icon of a Windows folder to increase its chance of user execution.
Installation
When run, the worm drops a copy of itself as the following file name:
 
%windir%\winlogon.exe
 
The registry is modified to run the worm copy at each Windows start.
 
In subkey: HKCU\Software\Microsoft\Windows\CurrentVersion\Run
Sets value: "winlogon.exe"
To data: "%windir%\winlogon.exe"
Spreads via…
Mapped network drives
The worm attempts to copy itself to mapped  network drives as the following:
  • <drive:>\.exe
  • <drive:>\winlogon.exe
  • <drive:>\subst\subst.exe
Additional information
The worm has the following file attributes that contribute to its detected name:
  • Product Name: poorvirus
 
Analysis by Jaime Wong

Symptoms

System changes
The following system changes may indicate the presence of this malware:
  • The presence of the following files located on mapped network drives:
    <drive:>\.exe
    <drive:>\winlogon.exe
    <drive:>\subst\subst.exe
  • Alert notifications from installed antivirus software may be the only other symptoms.

Prevention


Alert level: Severe
First detected by definition: 1.75.1155.0
Latest detected by definition: 1.175.527.0 and higher
First detected on: Feb 24, 2010
This entry was first published on: Oct 22, 2010
This entry was updated on: Apr 17, 2011

This threat is also detected as:
  • W32/VBTrojan.17E!Maximus (Command)
  • TR/Swisyn.C (Avira)
  • Backdoor.Agent.1 (BitDefender)
  • Win32/Swisyn.T (CA)
  • Win32/VB.NUV (ESET)
  • Trojan.Win32.Swisyn.ubp (Kaspersky)
  • Swisyn.e (McAfee)
  • Mal/VB-F (Sophos)
  • W32.SillyFDC (Symantec)
  • TROJ_SWISYN.AJ (Trend Micro)
  • Trojan.Swisyn.VJS (VirusBuster)