McAfee > Theat Center > Virus Detail Page

Overview

This is a virus detection. Viruses are programs that self-replicate recursively, meaning that infected systems spread the virus to other systems, which then propagate the virus further. While many viruses contain a destructive payload, it's quite common for viruses to do nothing more than spread from one system to another.

Characteristics

-- UPDATE July 17, 2001 --
A new variant of this worm, often using the filename, ms_v275657_x86_en.exe, was included in the 4148 DATs (released July 18).

There are three known components to this worm. BIN.DLL (22528 bytes) REGISTRY.DLL (54272 bytes) and an EXE (76800 bytes) which can have different names. All of these are packed with the UPX packer program.

When the EXE file is run, it copies itself to c:\WINDOWS\regsv.exe and creates a file called c:\WINDOWS\acI3.dll which contains what appears to be encrypted data. Note that though "c:\WINDOWS\" is used in this description, the directory may vary depending on what directory Windows was installed in.

It then creates the registry keys/valuse:

HKU\.Default\Software\Mirabilis\ICQ\Agent\Apps\icqrun="C:\WINDOWS\regsv.exe" HKLM\Software\Microsoft\Windows\CurrentVersion\Run\regsv="C:\WINDOWS\regsv.exe"

The following registry keys are created (which contain several subkeys which seem to be more encrypted data):

HKLM\SOFTWARE\Classes\Scandisk\i386\i\
HKLM\SOFTWARE\Classes\Scandisk\i386\s\

The EXE file also contains the master password to Subseven which it uses to infect other computers by running a portscan on multiple subnets, attempting to connect to TCP/IP port 27374. Once successfully connected to a Sub7 server, the worm files are copied to the remote system.

It also contains code to contact time servers and IRC servers, as well as download files over the web. Registry.dll also contains a mailing routine.

More recent variants of this worm also mail a bogus Microsoft Security Bulletin. Below is the actual mail message that is sent:

From: secnotif@MICROSOFT.COM
Subject:Microsoft Security Bulletin MS01-039
Message:

Symptoms

Presence of ACI3.DLL or regsv.exe

Method of Infection

This worm scans systems for the presence of the Subseven/BackDoor-G trojan and infects them if found.

Removal

All Users :
Script,Batch,Macro and non memory-resident:
Use current engine and DAT files for detection and removal.

PE,Trojan,Internet Worm and memory resident :
Use specified engine and DAT files for detection. To remove, boot to MS-DOS mode or use a boot diskette and use the command line scanner:

Additional Windows ME/XP removal considerations

Users should not trust file icons, particularly when receiving files from others via P2P clients, IRC, email or other mediums where users can share files.

AVERT Recommended Updates :

* Office2000 Updates

* Malformed Word Document Could Enable Macro to Run Automatically (Information/Patch )

* scriptlet.typelib/Eyedog vulnerability patch

* Outlook as an email attachment security update

* Exchange 5.5 post SP3 Information Store Patch 5.5.2652.42 - this patch corrects detection issues with GroupShield

For a list of attachments blocked by the Outlook patch and a general FAQ, visit this link .
Additionally, Network Administrators can configure this update using an available tool - visit this link for more information .

It is very common for macro viruses to disable options within Office applications for example in Word, the macro protection warning commonly is disabled. After cleaning macro viruses, ensure that your previously set options are again enabled.

Variants

Variants

All Information

Overview -

This is a virus detection. Viruses are programs that self-replicate recursively, meaning that infected systems spread the virus to other systems, which then propagate the virus further. While many viruses contain a destructive payload, it's quite common for viruses to do nothing more than spread from one system to another.

Characteristics

Characteristics -

-- UPDATE July 17, 2001 --
A new variant of this worm, often using the filename, ms_v275657_x86_en.exe, was included in the 4148 DATs (released July 18).

There are three known components to this worm. BIN.DLL (22528 bytes) REGISTRY.DLL (54272 bytes) and an EXE (76800 bytes) which can have different names. All of these are packed with the UPX packer program.

When the EXE file is run, it copies itself to c:\WINDOWS\regsv.exe and creates a file called c:\WINDOWS\acI3.dll which contains what appears to be encrypted data. Note that though "c:\WINDOWS\" is used in this description, the directory may vary depending on what directory Windows was installed in.

It then creates the registry keys/valuse:

HKU\.Default\Software\Mirabilis\ICQ\Agent\Apps\icqrun="C:\WINDOWS\regsv.exe" HKLM\Software\Microsoft\Windows\CurrentVersion\Run\regsv="C:\WINDOWS\regsv.exe"

The following registry keys are created (which contain several subkeys which seem to be more encrypted data):

HKLM\SOFTWARE\Classes\Scandisk\i386\i\
HKLM\SOFTWARE\Classes\Scandisk\i386\s\

The EXE file also contains the master password to Subseven which it uses to infect other computers by running a portscan on multiple subnets, attempting to connect to TCP/IP port 27374. Once successfully connected to a Sub7 server, the worm files are copied to the remote system.

It also contains code to contact time servers and IRC servers, as well as download files over the web. Registry.dll also contains a mailing routine.

More recent variants of this worm also mail a bogus Microsoft Security Bulletin. Below is the actual mail message that is sent:

From: secnotif@MICROSOFT.COM
Subject:Microsoft Security Bulletin MS01-039
Message:

Symptoms

Symptoms -

Presence of ACI3.DLL or regsv.exe

Method of Infection

Method of Infection -

This worm scans systems for the presence of the Subseven/BackDoor-G trojan and infects them if found.

Removal -

Removal -

All Users :
Script,Batch,Macro and non memory-resident:
Use current engine and DAT files for detection and removal.

PE,Trojan,Internet Worm and memory resident :
Use specified engine and DAT files for detection. To remove, boot to MS-DOS mode or use a boot diskette and use the command line scanner:

Additional Windows ME/XP removal considerations

Users should not trust file icons, particularly when receiving files from others via P2P clients, IRC, email or other mediums where users can share files.

AVERT Recommended Updates :

* Office2000 Updates

* Malformed Word Document Could Enable Macro to Run Automatically (Information/Patch )

* scriptlet.typelib/Eyedog vulnerability patch

* Outlook as an email attachment security update

* Exchange 5.5 post SP3 Information Store Patch 5.5.2652.42 - this patch corrects detection issues with GroupShield

For a list of attachments blocked by the Outlook patch and a general FAQ, visit this link .
Additionally, Network Administrators can configure this update using an available tool - visit this link for more information .

It is very common for macro viruses to disable options within Office applications for example in Word, the macro protection warning commonly is disabled. After cleaning macro viruses, ensure that your previously set options are again enabled.

Variants

Variants -