Jump Virus
Virus Name: Jump
Aliases: Jump.466
V Status: New
Discovered: October, 1994
Symptoms: .COM file growth; file date/time changes;
decrease in total system & available free memory
Origin: Unknown
Eff Length: 466 Bytes
Type Code: PRhC - Parasitic Resident .COM Infector
Detection Method: AVTK, ViruScan, IBMAV, Sweep, F-Prot, NAV,
NAVDX, PCScan, ChAV,
Sweep/N, IBMAV/N, NShld, AVTK/N, NAV/N, Innoc 4.0+
Removal Instructions: Delete infected files
General Comments:
The Jump or Jump.466 virus was received in October, 1994. Its origin
or point of isolation is unknown. Jump is a memory resident infector
of .COM files, though it does not infect all .COM files.
When the first Jump infected program is executed, this virus will
install itself memory resident at the top of system memory but below
the 640K DOS boundary, not moving interrupt 12's return. Total
system and available free memory, as indicated by the DOS CHKDSK
program, will have decreased by 768 bytes. Interrupt 21 will be
hooked by the virus in memory.
Once the Jump virus is memory resident, it may infect .COM files
when they are executed. Infected programs will have a file length
increase of 466 bytes with the virus being located at the end of the
file. The program's date and time in the DOS disk directory
listing will have been updated to the current system date and time.
The following text string is visible within the viral code in all
infected programs:
"JUMP"