Chromo 1.0 Virus
Virus Name: Chromo 1.0
Aliases:
V Status: Rare
Discovery: June, 1993
Symptoms: .COM file growth
Origin: Unknown
Eff Length: 406 Bytes
Type Code: PNC - Parasitic Non-Resident .COM Infector
Detection Method: ViruScan, F-Prot, IBMAV, AVTK, Sweep,
NAV, NAVDX, VAlert, PCScan, ChAV,
NShld, NProt, AVTK/N, Sweep/N, IBMAV/N, Innoc, NAV/N,
LProt
Removal Instructions: Delete infected files
General Comments:
The Chromo 1.0 virus was submitted in June, 1993. Its origin or
point of isolation is unknown. Chromo 1.0 is a non-resident infector
of .COM programs, but not COMMAND.COM. It does not infect very
small .COM programs.
When a program infected with the Chromo 1.0 virus is executed, this
virus will infect three .COM programs located in the current or a
higher level directory. Infected programs will have a file length
increase of 406 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 not be altered. The following text strings are visible within
the viral code in all Chromo 1.0 infected programs:
"*.COM .. [Chromosome Glitch] v1.0"
"Copyright (c) 1993 Memory Lapse."
It is unknown what Chromo 1.0 does besides replicate.
Known variant(s) of Chromo 1.0 are:
Chromo 2.0: Received in July, 1993, Chromo 2.0 is a 407 byte
variant of the Chromo 1.0 virus described above. This
variant infects three .EXE files in the current or a
higher level directory when an infected program is
executed. Infected programs will have a file length
increase of 407 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 not be altered.
The following text strings can be found within the
viral code in all Chromo 2.0 infected programs:
"*M.EXE .. [Chromosome Glitch] v2.0"
"Copyright (c) 1993 Memory Lapse."
Origin: Unknown July, 1993.
Chromo 3.0: Received in August, 1993, Chromo 3.0 is a memory
resident variant of the Chromo 1.0 and Chromo 2.0
viruses. It becomes memory resident at the top of
system memory but below the 640K DOS boundary when the
first infected program is executed. Total system and
available free memory, as indicated by the DOS CHKDSK
program, will have decreased by 672 bytes, interrupt
21 will be hooked. Once it is memory resident, Chromo
3.0 will infect .COM programs when they are executed.
Infected programs will have a file length increase of
385 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 not be altered. The following
text strings are visible within all Chromo 3.0 infected
files:
"[Chromosome Glitch] v3.0"
"Copyright (c) 1993 Memory Lapse."
Origin: Unknown August, 1993.
See: Memory Lapse