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

Timor is a memory resident, file infecting virus. It infects .COM and .EXE files, and is based on the Jerusalem virus.

Upon infection, the Timor virus becomes memory resident as a low system memory Terminate-and-Stay Resident (TSR) of 2,816 bytes. It hooks interrupts 21 and F8.

Once memory resident, it infects .COM and .EXE files as they are executed.

Additional Comments:
The Timor virus was received in April, 1992. Its origin is unknown. Timor is a memory resident infector of .COM and .EXE programs, and is based on the Jerusalem virus. When the first Timor infector program is executed, the Timor virus will install itself memory resident as a low system memory TSR of 2,816 bytes. It will hook interrupts 21 and F8. Once Timor is memory resident, it will infect .COM and .EXE programs when they are executed. .COM programs will have a file length increase of 1,562 bytes with the virus being located at the beginning of the infected file. .EXE programs will have a file length increase of 1,562 - 1,576 bytes with the virus being located at the end of the infected file. Unlike Jerusalem, Timor does not reinfect .EXE files. Infected programs will not have any change to their date and time in the DOS disk directory. The following text strings can be found in all Timor infected programs: "Timor" "St Cruz, Dili" "COMMAND.COM" "LxTimor" "sso, Freedom for East Timor !" "1991 Nov 12, Lusit`xff`x83ia Expres" Timor activates on November 12th of any year, at which time it may display the message: "St Cruz, Dili".

Symptoms

The following text strings are found in all Timor infected files:

"Timor"
"St Cruz, Dili"
"COMMAND.COM"
"LxTimor"
"sso, Freedom for East Timor !"
"1991 Nov 12, Lusit`xff`x83ia Expres"

Timor activates on November 12th of any year, at which time it may display the message: "St Cruz, Dili".

Infected .COM files have a file length increase of 1,562 bytes. The virus is located at the beginning of the infected file. Infected .EXE files have a file length increase of 1,562 - 1,576 bytes. The virus is located at the end of the infected file. Infected files do not have any change to their date and time in the DOS disk directory.

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

N/A

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 -

Timor is a memory resident, file infecting virus. It infects .COM and .EXE files, and is based on the Jerusalem virus.

Upon infection, the Timor virus becomes memory resident as a low system memory Terminate-and-Stay Resident (TSR) of 2,816 bytes. It hooks interrupts 21 and F8.

Once memory resident, it infects .COM and .EXE files as they are executed.

Additional Comments:
The Timor virus was received in April, 1992. Its origin is unknown. Timor is a memory resident infector of .COM and .EXE programs, and is based on the Jerusalem virus. When the first Timor infector program is executed, the Timor virus will install itself memory resident as a low system memory TSR of 2,816 bytes. It will hook interrupts 21 and F8. Once Timor is memory resident, it will infect .COM and .EXE programs when they are executed. .COM programs will have a file length increase of 1,562 bytes with the virus being located at the beginning of the infected file. .EXE programs will have a file length increase of 1,562 - 1,576 bytes with the virus being located at the end of the infected file. Unlike Jerusalem, Timor does not reinfect .EXE files. Infected programs will not have any change to their date and time in the DOS disk directory. The following text strings can be found in all Timor infected programs: "Timor" "St Cruz, Dili" "COMMAND.COM" "LxTimor" "sso, Freedom for East Timor !" "1991 Nov 12, Lusit`xff`x83ia Expres" Timor activates on November 12th of any year, at which time it may display the message: "St Cruz, Dili".

Symptoms

Symptoms -

The following text strings are found in all Timor infected files:

"Timor"
"St Cruz, Dili"
"COMMAND.COM"
"LxTimor"
"sso, Freedom for East Timor !"
"1991 Nov 12, Lusit`xff`x83ia Expres"

Timor activates on November 12th of any year, at which time it may display the message: "St Cruz, Dili".

Infected .COM files have a file length increase of 1,562 bytes. The virus is located at the beginning of the infected file. Infected .EXE files have a file length increase of 1,562 - 1,576 bytes. The virus is located at the end of the infected file. Infected files do not have any change to their date and time in the DOS disk directory.

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 -

N/A