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

• LK

• Mithrandrill

Characteristics

LockUp is a memory resident, spawning, stealth, file infecting virus. It infects .EXE files. LockUp uses stealth techniques to avoid detection.

Upon infection, the 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 LockUp in memory.

Once the LockUp virus is memory resident, it infects .EXE files as they are opened or executed.

Additional Comments:
The LockUp virus was isolated in Sweden in May, 1992. This virus is a memory resident spawning or companion virus which infects .EXE programs, and uses some stealth techniques to avoid detection. The first time a program infected with the LockUp virus is executed, the virus will 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 1,568 bytes. Interrupt 21 will be hooked by LockUp in memory. Once the LockUp virus is memory resident, it will infect .EXE programs when they are opened or executed. Infected .EXE programs are not altered, but rather the virus creates a hidden 496 bytes .COM file in the directory with the same base file name. These hidden files always have the file date and time of 3-24-23 2:17a in the DOS disk directory. After the virus has created the hidden file, any time the user attempts to execute the infected .EXE program, the companion .COM program will be executed by DOS. The following text strings can be found in the 496 byte companion .COM files created by the LockUp virus: "DeMoRaLiZeD YoUtH" "Mithrandir III" When the LockUp virus is memory resident, it attempts to mask the presence of the hidden .COM files in order to avoid detection by anti-viral programs. The programs may not see the hidden files, so no virus will be found. Known variant(s) of LockUp are:

Symptoms

The following text strings are found in the 496 byte companion .COM files created by the LockUp virus:

"DeMoRaLiZeD YoUtH"
"Mithrandir III"

Total system and available free memory decreases by 1,024 bytes. Infected .EXE files are not altered, but rather the virus creates a hidden 496 bytes .COM file in the directory with the same base file name. These hidden files always have the file date and time of 3-24-23 2:17a in the DOS disk directory. After the virus has created the hidden file, any time the user attempts to execute the infected .EXE file, the companion .COM file is executed by DOS.

When the LockUp virus is memory resident, it attempts to mask the presence of the hidden .COM files in order to avoid detection by anti-viral files (Stealth techniques).

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

• LockUp-B

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

• LK

• Mithrandrill

Characteristics

Characteristics -

LockUp is a memory resident, spawning, stealth, file infecting virus. It infects .EXE files. LockUp uses stealth techniques to avoid detection.

Upon infection, the 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 LockUp in memory.

Once the LockUp virus is memory resident, it infects .EXE files as they are opened or executed.

Additional Comments:
The LockUp virus was isolated in Sweden in May, 1992. This virus is a memory resident spawning or companion virus which infects .EXE programs, and uses some stealth techniques to avoid detection. The first time a program infected with the LockUp virus is executed, the virus will 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 1,568 bytes. Interrupt 21 will be hooked by LockUp in memory. Once the LockUp virus is memory resident, it will infect .EXE programs when they are opened or executed. Infected .EXE programs are not altered, but rather the virus creates a hidden 496 bytes .COM file in the directory with the same base file name. These hidden files always have the file date and time of 3-24-23 2:17a in the DOS disk directory. After the virus has created the hidden file, any time the user attempts to execute the infected .EXE program, the companion .COM program will be executed by DOS. The following text strings can be found in the 496 byte companion .COM files created by the LockUp virus: "DeMoRaLiZeD YoUtH" "Mithrandir III" When the LockUp virus is memory resident, it attempts to mask the presence of the hidden .COM files in order to avoid detection by anti-viral programs. The programs may not see the hidden files, so no virus will be found. Known variant(s) of LockUp are:

Symptoms

Symptoms -

The following text strings are found in the 496 byte companion .COM files created by the LockUp virus:

"DeMoRaLiZeD YoUtH"
"Mithrandir III"

Total system and available free memory decreases by 1,024 bytes. Infected .EXE files are not altered, but rather the virus creates a hidden 496 bytes .COM file in the directory with the same base file name. These hidden files always have the file date and time of 3-24-23 2:17a in the DOS disk directory. After the virus has created the hidden file, any time the user attempts to execute the infected .EXE file, the companion .COM file is executed by DOS.

When the LockUp virus is memory resident, it attempts to mask the presence of the hidden .COM files in order to avoid detection by anti-viral files (Stealth techniques).

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 -

• LockUp-B