Virus.MSOffice.Halfcros

Parent class: VirWare

Viruses and worms are malicious programs that self-replicate on computers or via computer networks without the user being aware; each subsequent copy of such malicious programs is also able to self-replicate. Malicious programs which spread via networks or infect remote machines when commanded to do so by the “owner” (e.g. Backdoors) or programs that create multiple copies that are unable to self-replicate are not part of the Viruses and Worms subclass. The main characteristic used to determine whether or not a program is classified as a separate behaviour within the Viruses and Worms subclass is how the program propagates (i.e. how the malicious program spreads copies of itself via local or network resources.) Most known worms are spread as files sent as email attachments, via a link to a web or FTP resource, via a link sent in an ICQ or IRC message, via P2P file sharing networks etc. Some worms spread as network packets; these directly penetrate the computer memory, and the worm code is then activated. Worms use the following techniques to penetrate remote computers and launch copies of themselves: social engineering (for example, an email message suggesting the user opens an attached file), exploiting network configuration errors (such as copying to a fully accessible disk), and exploiting loopholes in operating system and application security. Viruses can be divided in accordance with the method used to infect a computer:

• file viruses
• boot sector viruses
• macro viruses
• script viruses

Any program within this subclass can have additional Trojan functions. It should also be noted that many worms use more than one method in order to spread copies via networks.

Class: Virus

Viruses replicate on the resources of the local machine. Unlike worms, viruses do not use network services to propagate or penetrate other computers. A copy of a virus will reach remote computers only if the infected object is, for some reason unrelated to the virus function, activated on another computer. For example: when infecting accessible disks, a virus penetrates a file located on a network resource a virus copies itself to a removable storage device or infects a file on a removable device a user sends an email with an infected attachment.

Read more

Platform: MSOffice

Microsoft Office is a multiplatform suite of productivity applications published by Microsoft. Office applications are compatible with many types of files and content.

Description

This is multi-platform macro-virus. It infects two MS Office97 applications: Word documents and Excel sheets. The main part of the virus code is encrypted and placed in the virus body as a random-letters comments. In case of need, the virus gets these comments, decrypts them, convert to the macro instructions and executes them. As a result, the main replication routines are invisible by viewing macro code in the Tools/Macro menu.

In non-encrypted form, there are just a few virus macros present: events hookers and decryption routine. The virus hooks three events: Excel sheets closing, and Word documents opening and closing (Workbook_Deactivate, Document_Open, Document_Close). In all these cases, the virus decrypts and calls the infection routine. The virus also creates the infected BOOK1 Excel sheet in the Excel auto-start directory.

The virus disables the MS Office virus protection by directly accessing the system registry. Starting from 0:10pm till 0:25pm, the virus displays the message box:

Wonder v2.0 by ThE wEiRd GeNiUs



Its time for lunch 

where is the name of current user.

Read more

Find out the statistics of the vulnerabilities spreading in your region on statistics.securelist.com