WM/MERCY.B

This page shows details and results of our analysis on the malware WM/MERCY.B

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.


Minimum DAT

4002 (1998-12-02)

Updated DAT

4002 (1998-12-02)

Minimum Engine

5400.1158

File Length

Not Applicable

Description Added

1997-05-15

Description Modified

1997-05-15

Malware Proliferation

Characteristics

This virus propagates by infecting Word Documents in Microsoft WORD Versions 6.x / 7.x on Windows and Macintosh platforms. The virus consists of these macros:

AUTOEXEC, AUTOOPEN, *, *, * (WHERE * IS A RANDOMLY GENERATED NAME CONSISTING OF CAPITAL LETTERS)

in an infected document. Their names change to:

AUTOCLOSE, *, *, TOOLSMACRO, FILETEMPLATES, ORGANIZER (WHERE * IS A RANDOMLY GENERATED NAME CONSISTING OF CAPITAL LETTERS)

in Word's Global Template NORMAL.DOT. The virus becomes active by using AutoMacros. All macros are encrypted using the standard Word execute-only feature. Meaning that the user is unable to edit or view the macro code.

Symptoms

On an infected system the virus hides the FILE|TEMPLATE, TOOLS|MACRO, ORGANIZER and functionality. Warning: It is important not to use these commands, as you will execute the viral code.

When opening a file on the 11th of any month, a MessageBox like

- Espisode 2: TenFaces (The Series continue . . .) X

The 10Faces is back! Hey Avers the name is 10Faces!! Not Mercy.A - c reator of NoMercy-


OK

is displayed.

Method of Infection

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:

SCANPM /ADL /CLEAN /ALL

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