WORM_OTORUN.ROS
Windows 2000, XP, Server 2003
Threat Type: Worm
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
Propagates via IRC, Propagates via removable drives
This worm arrives via removable drives. It may be downloaded by other malware/grayware/spyware from remote sites. It may be unknowingly downloaded by a user while visiting malicious websites.
It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.
It connects to Internet Relay Chat (IRC) servers. It joins an Internet Relay Chat (IRC) channel.
TECHNICAL DETAILS
18,482 bytes
EXE
Yes
16 Nov 2010
Joins an Internet Relay Chat (IRC) channel
Arrival Details
This worm arrives via removable drives.
It may be downloaded by other malware/grayware/spyware from remote sites.
It may be unknowingly downloaded by a user while visiting malicious websites.
Installation
This worm drops the following component file(s):
- [drive letter]:\RESTORE\{SID}\Desktop.ini
It drops the following copies of itself into the affected system:
- [drive letter]:\RESTORE\{SID}\DriveFix.exe
It creates the following folders:
- %System Root%:\RESTORE\{SID}
- %System Root%:\RESTORE
(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)
It stays memory-resident by injecting codes into the following processes:
- Explorer.exe
Autostart Technique
This worm adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{28ABC5C0-4FCB-11CF-AAX5-21CX1C987192}
StubPath = %System Root%:\RESTORE\{SID}\DriveFix.exe
Other System Modifications
This worm adds the following registry keys:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{28ABC5C0-4FCB-11CF-AAX5-21CX1C987192}
Propagation
This worm creates the following folders in all removable drives:
- [drive letter]:\RESTORE\{SID}
- [drive letter]:\RESTORE
It drops the following copy(ies) of itself in all removable drives:
- [drive letter]:\RESTORE\{SID}\DriveFix.exe
It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.
The said .INF file contains the following strings:
[autorun]
open=RESTORE\{SID}\DriveFix.exe
icon=%SystemRoot%\system32\SHELL32.dll,4
action=Open folder to view files
shell\open=Open
shell\open\command=RESTORE\{SID}\DriveFix.exe
Backdoor Routine
This worm connects to any of the following Internet Relay Chat (IRC) servers:
- {BLOCKED}er.net
It joins any of the following Internet Relay Chat (IRC) channels:
- #l4mer#
SOLUTION
8.900
7.624.00
16 Nov 2010
Step 1
For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.
Step 2
Restart in Safe Mode
Step 3
Delete this registry key
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Active Setup\Installed Components
- {28ABC5C0-4FCB-11CF-AAX5-21CX1C987192}
- {28ABC5C0-4FCB-11CF-AAX5-21CX1C987192}
Step 4
Search and delete these folders
Step 5
Search and delete AUTORUN.INF files created by WORM_OTORUN.ROS that contain these strings
Step 6
Restart in normal mode and scan your computer with your Trend Micro product for files detected as WORM_OTORUN.ROS. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.
Did this description help? Tell us how we did.