Content
Jerusalem
- Type
- Virus
- SubType
- File Infector
- Discovery Date
- 10/01/1987
- Length
- 1,808-1,822 Bytes
- Minimum DAT
- 4002 (12/02/1998)
- Updated DAT
- 4342 (03/24/2004)
- Minimum Engine
- 5.1.00
- Description Added
- 10/15/1987
- Description Modified
- 10/15/1987 12:00 AM (PT)
Tab Navigation
Characteristics
Jerusalem is a memory resident, file infecting virus. Jerusalem infects .COM, .EXE, .SYS, .BIN, .PIF, and .OVL files. Jerusalem does not infect COMMAND.COM. The Jerusalem virus is thought to have been based on the Suriv 3.00 virus, though the Suriv 3.00 virus was isolated after the Jerusalem virus. The Jerusalem virus has been altered many times, and many other viruses have been based on its code. The description below is for a standard Jerusalem virus.
Upon infection, the Jerusalem virus becomes memory resident as a low system memory Terminate-and-Stay Resident (TSR) of 1,792 bytes. Interrupts 08 and 21 are hooked by the Jerusalem virus in memory.
Once the Jerusalem virus is memory resident, it infects files other than COMMAND.COM as they are executed. The Jerusalem virus may reinfect .EXE files due to a bug in the viral code.
Additional Comments:
The Jerusalem virus was originally isolated at Hebrew University in
Israel in the Fall of 1987. As of November, 1991, it is thought to
have now originated in Italy. Jerusalem is a memory resident
generic file infector. Jerusalem viruses will infect .COM, .EXE,
.SYS, .BIN, .PIF, and overlay files when they are executed .EXE
files may be reinfected by the virus each time they are executed due
to a bug in the viral code. The Jerusalem virus has been altered
many times, and many other viruses have been based on its code. The
description below is for a standard Jerusalem virus which reinfects
.EXE files when they are executed. Other variants, or members of
this family, are indicated below.
The first time a program infected with the Jerusalem virus is
executed, the Jerusalem virus will install itself memory resident
as a low system memory TSR of 1,792 bytes. Interrupts 08 and 21
will be hooked by the Jerusalem virus in memory.
Once the Jerusalem virus is memory resident, it will infect programs
other than COMMAND.COM when they are executed. .COM programs will
increase in size by 1,813 bytes with the virus being located at the
beginning of the infected file. .EXE programs will increase in
size by 1,808 to 1,822 bytes with the virus being located at the
end of the infected file. Later, infected .EXE programs will be
reinfected by the virus when they are again executed. Each
reinfection will add an additional 1,808 bytes to the file.
Jerusalem infected programs will have no change to their date and
time in the DOS disk directory.
This virus redirects interrupt 8, and 1/2 hour after execution of the
first infected program the system will slow down by a factor of 10.
Additionally, some Jerusalem virus variants will have a "black
window" or "black box" appear on the lower left side of the screen
which will scroll up the screen as the screen scrolls.
The Jerusalem virus activates after it becomes memory resident on
Friday the 13ths. At that time, it will delete any program the user
attempts to execute.
The identifier for most Jerusalem strains is "sUMsDos", however, this
identifier may not be found in the newer variants of Jerusalem.
The Jerusalem virus is thought to have been based on the Suriv 3.00
virus, though the Suriv 3.00 virus was isolated after the Jerusalem
virus.
Known members(s) of the Jerusalem Family are:
Symptoms
Infected .COM files increase in size by 1,813 bytes. The virus is located at the beginning of the infected file. .EXE files increase in size by 1,808 to 1,822 bytes. The virus is located at the end of the infected file. Each reinfection adds an additional 1,808 bytes to the .EXE file. Jerusalem infected files have no change to their date and time in the DOS disk directory.
This virus redirects interrupt 8, and 1/2 hour after execution of the first infected file the system slows down by a factor of 10.
Additionally, some Jerusalem virus variants have a "black window" or "black box" appear on the lower left side of the screen which scrolls up the screen as the screen scrolls.
The Jerusalem virus activates after it becomes memory resident on Friday the 13th. At that time, it deletes any file the user attempts to execute.
The identifier for most Jerusalem strains is "sUMsDos", however, this identifier may not be found in the newer variants of Jerusalem.
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 :
* 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.
Aliases
- 1808(EXE)
- 1813(COM)
- ArabStar
- BlackBox
- BlackWindow
- Friday13th
- HebrewUniversity
- Israeli
- PLO
- Russian
Characteristics
Characteristics -
Jerusalem is a memory resident, file infecting virus. Jerusalem infects .COM, .EXE, .SYS, .BIN, .PIF, and .OVL files. Jerusalem does not infect COMMAND.COM. The Jerusalem virus is thought to have been based on the Suriv 3.00 virus, though the Suriv 3.00 virus was isolated after the Jerusalem virus. The Jerusalem virus has been altered many times, and many other viruses have been based on its code. The description below is for a standard Jerusalem virus.
Upon infection, the Jerusalem virus becomes memory resident as a low system memory Terminate-and-Stay Resident (TSR) of 1,792 bytes. Interrupts 08 and 21 are hooked by the Jerusalem virus in memory.
Once the Jerusalem virus is memory resident, it infects files other than COMMAND.COM as they are executed. The Jerusalem virus may reinfect .EXE files due to a bug in the viral code.
Additional Comments:
The Jerusalem virus was originally isolated at Hebrew University in
Israel in the Fall of 1987. As of November, 1991, it is thought to
have now originated in Italy. Jerusalem is a memory resident
generic file infector. Jerusalem viruses will infect .COM, .EXE,
.SYS, .BIN, .PIF, and overlay files when they are executed .EXE
files may be reinfected by the virus each time they are executed due
to a bug in the viral code. The Jerusalem virus has been altered
many times, and many other viruses have been based on its code. The
description below is for a standard Jerusalem virus which reinfects
.EXE files when they are executed. Other variants, or members of
this family, are indicated below.
The first time a program infected with the Jerusalem virus is
executed, the Jerusalem virus will install itself memory resident
as a low system memory TSR of 1,792 bytes. Interrupts 08 and 21
will be hooked by the Jerusalem virus in memory.
Once the Jerusalem virus is memory resident, it will infect programs
other than COMMAND.COM when they are executed. .COM programs will
increase in size by 1,813 bytes with the virus being located at the
beginning of the infected file. .EXE programs will increase in
size by 1,808 to 1,822 bytes with the virus being located at the
end of the infected file. Later, infected .EXE programs will be
reinfected by the virus when they are again executed. Each
reinfection will add an additional 1,808 bytes to the file.
Jerusalem infected programs will have no change to their date and
time in the DOS disk directory.
This virus redirects interrupt 8, and 1/2 hour after execution of the
first infected program the system will slow down by a factor of 10.
Additionally, some Jerusalem virus variants will have a "black
window" or "black box" appear on the lower left side of the screen
which will scroll up the screen as the screen scrolls.
The Jerusalem virus activates after it becomes memory resident on
Friday the 13ths. At that time, it will delete any program the user
attempts to execute.
The identifier for most Jerusalem strains is "sUMsDos", however, this
identifier may not be found in the newer variants of Jerusalem.
The Jerusalem virus is thought to have been based on the Suriv 3.00
virus, though the Suriv 3.00 virus was isolated after the Jerusalem
virus.
Known members(s) of the Jerusalem Family are:
Symptoms
Symptoms -
Infected .COM files increase in size by 1,813 bytes. The virus is located at the beginning of the infected file. .EXE files increase in size by 1,808 to 1,822 bytes. The virus is located at the end of the infected file. Each reinfection adds an additional 1,808 bytes to the .EXE file. Jerusalem infected files have no change to their date and time in the DOS disk directory.
This virus redirects interrupt 8, and 1/2 hour after execution of the first infected file the system slows down by a factor of 10.
Additionally, some Jerusalem virus variants have a "black window" or "black box" appear on the lower left side of the screen which scrolls up the screen as the screen scrolls.
The Jerusalem virus activates after it becomes memory resident on Friday the 13th. At that time, it deletes any file the user attempts to execute.
The identifier for most Jerusalem strains is "sUMsDos", however, this identifier may not be found in the newer variants of Jerusalem.
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 :
* 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