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.

Aliases

• Baobab

• Fva.1635

Characteristics

Baobab.1635 is a memory resident, file infecting virus. It infects .EXE files.

Upon infection, the Baobab.1635 virus becomes memory resident at the top of system memory but below the 640K DOS boundary. It does not move interrupt 12's return. Interrupt 21 is hooked by the Baobab.1635 virus in memory.

Once the Baobab.1635 virus is memory resident, it infects .EXE files as they are executed.

It is not known what Baobab.1635 may do besides replicate.

Additional Comments:
The Baobab virus was received in July, 1992. It is originally from India. Baobab is a memory resident infector of .EXE programs. When the first Baobab infected program is executed, the Baobab virus will install itself memory resident at the top of system memory but below the 640K DOS boundary. It does not move interrupt 12's return. Total system and available free memory, as indicated by the DOS CHKDSK program, will have decreased by 2,560 bytes. Interrupt 21 will be hooked by the Baobab virus in memory. Once the Baobab virus is memory resident, it will infect .EXE programs when they are executed. Infected programs will have a file length increase of 1,641 to 1,651 bytes with the virus being located at the end of the infected file. The Baobab virus will reinfect previously infected programs, adding an additional 1,648 bytes with each reinfection. Infected programs will have their date and time in the DOS disk directory listing altered to the current system date and time when the last infection of the file occurred. It is unknown what Baobab may do besides replicate. Known variant(s) of Baobab are:

Symptoms

Total system and available free memory decreases by 2,560 bytes. Infected files have a file length increase of 1,635 bytes. The virus is located at the end of the infected file. The Baobab.1635 virus reinfects previously infected files, adding an additional 1,635 bytes with each reinfection. Infected files have their date and time in the DOS disk directory listing altered to the current system date and time when the last infection of the file occurred.

Method of Infection

The only way to infect a computer with a file infecting virus is to execute an infected file on the computer. The infected file may come from a multitude of sources including: floppy diskettes, downloads through an online service, network, etc. Once the infected file is executed, the virus may activate.

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

• Baobab.731
• Baobob.2304
• Baobab.2312
• SillyRE-2304

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.

Aliases

• Baobab

• Fva.1635

Characteristics

Characteristics -

Baobab.1635 is a memory resident, file infecting virus. It infects .EXE files.

Upon infection, the Baobab.1635 virus becomes memory resident at the top of system memory but below the 640K DOS boundary. It does not move interrupt 12's return. Interrupt 21 is hooked by the Baobab.1635 virus in memory.

Once the Baobab.1635 virus is memory resident, it infects .EXE files as they are executed.

It is not known what Baobab.1635 may do besides replicate.

Additional Comments:
The Baobab virus was received in July, 1992. It is originally from India. Baobab is a memory resident infector of .EXE programs. When the first Baobab infected program is executed, the Baobab virus will install itself memory resident at the top of system memory but below the 640K DOS boundary. It does not move interrupt 12's return. Total system and available free memory, as indicated by the DOS CHKDSK program, will have decreased by 2,560 bytes. Interrupt 21 will be hooked by the Baobab virus in memory. Once the Baobab virus is memory resident, it will infect .EXE programs when they are executed. Infected programs will have a file length increase of 1,641 to 1,651 bytes with the virus being located at the end of the infected file. The Baobab virus will reinfect previously infected programs, adding an additional 1,648 bytes with each reinfection. Infected programs will have their date and time in the DOS disk directory listing altered to the current system date and time when the last infection of the file occurred. It is unknown what Baobab may do besides replicate. Known variant(s) of Baobab are:

Symptoms

Symptoms -

Total system and available free memory decreases by 2,560 bytes. Infected files have a file length increase of 1,635 bytes. The virus is located at the end of the infected file. The Baobab.1635 virus reinfects previously infected files, adding an additional 1,635 bytes with each reinfection. Infected files have their date and time in the DOS disk directory listing altered to the current system date and time when the last infection of the file occurred.

Method of Infection

Method of Infection -

The only way to infect a computer with a file infecting virus is to execute an infected file on the computer. The infected file may come from a multitude of sources including: floppy diskettes, downloads through an online service, network, etc. Once the infected file is executed, the virus may activate.

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 -

• Baobab.731
• Baobob.2304
• Baobab.2312
• SillyRE-2304