Tiny Virus Virus
Virus Name: Tiny Virus
Aliases: Danish Tiny, 163 COM Virus, Tiny 163 Virus
V Status: Rare
Discovery: June, 1990
Symptoms: COMMAND.COM & .COM file growth
Origin: Denmark
Eff Length: 163 Bytes
Type Code: PNCK - Parasitic Non-Resident .COM Infector
Detection Method: ViruScan, F-Prot, NAV, AVTK, Sweep, IBMAV,
NAVDX, VAlert, PCScan, ChAV,
NShld, LProt, Sweep/N, Innoc, NProt, AVTK/N,
NAV/N, IBMAV/N
Removal Instructions: F-Prot, or delete infected files
General Comments:
The 163 COM Virus, or Tiny Virus, was isolated by Fridrik Skulason
of Iceland in June 1990. This virus is a non-resident generic .COM
file infector, and it will infect COMMAND.COM.
The first time a file infected with the 163 COM Virus is executed,
the virus will attempt to infect the first .COM file in the current
directory. On bootable diskettes, this file will normally be
COMMAND.COM. After the first .COM file is infected, each time an
infected program is executed another .COM file will attempt to be
infected. Files are infected only if their original length is
greater than approximately 1K bytes.
Infected .COM files will increase in length by 163 bytes, and have
date/time stamps in the directory changed to the date/time the
infection occurred. Infected files will also always end with this
hex string: '2A2E434F4D00'.
This virus currently does nothing but replicate, and is the
smallest MS-DOS virus known as of its isolation date.
The Tiny Virus may or may not be related to the Tiny Family
documented elsewhere in this listing.
Known variant(s) of the Tiny Virus are:
191: A 191 byte variant of the Tiny Virus, the 191 virus will
infect one .COM file in the current directory each time an
infected program is executed. Infected programs will have a
file length increase of 191 bytes with the virus being located
at the end of the file. The file's date and time in the DOS
disk directory listing will not be altered. One text string
occurs in the viral code:
"*.COM"
The 191 virus does not infect very small files, and it will
usually not infect more than four files in the current
directory. It does nothing besides replicate.
Origin: Unknown December, 1991.
Brenda: A 256 byte variant of the Tiny Virus, Brenda infects
one .COM file in the current directory when an infected program
is executed. Infected programs will have a file length increase
of 256 bytes with the virus being located at the end of the
infected file. The program's date and time in the DOS disk
directory listing will be updated to the current system date and
time when infection occurred. After Brenda has infected the
first three .COM files in the current directory, it will display
the following message instead of infecting a file when an
infected program is executed:
"(C) '92, Stingray/VIPER
Luv, Brenda"
This message is not visible in infected files as it is
encrypted. One text string is visible within the Brenda virus
viral code: "*.COM".
Origin: Unknown May, 1992.
Brenda-B: Functionally similar to Brenda, this variant has one
byte which has been altered.
Origin: Unknown October, 1992.
Danish Tiny.476: A 476 byte variant of the Tiny Virus, this
virus will infect one .COM file in the current directory each
time an infected program is executed. Infected programs will
have a file length increase of 476 bytes with the virus being
located at the end of the file. The file's date and time in
the DOS disk directory listing will not be altered. The
following text is encrypted within the viral code:
"*.COM .."
"EW_476 MM2 VIRUS\MYVIRII\TEMP ge by the BLACK WIND VIRUS..."
"Copyright (C) 1992, Destructive Technologies, Unlimited."
Origin: Unknown July, 1994.
Danish Tiny.NC.284: A 284 byte variant of the Tiny Virus, this
virus will infect the first .COM file in the current directory
each time an infected program is executed. Infected programs
will have a file length increase of 284 bytes with the virus
being located at the end of the file. The file's date and time
in the DOS disk directory listing will not be altered. The
following text is visible within the viral code:
"*.*"
"***NIGHTCRAWLER V 2.0 ***"
"Written by the Weasel! (C) Sector Infector Inc"
This variant will reinfect previously infected files, adding an
additional 284 bytes with each reinfection.
Origin: Unknown July, 1994.
Kennedy: The Kennedy virus is a 333 byte variant of the Tiny
virus. It infects one .COM program when an infected program
is executed, adding 333 bytes to the end of the file. This
virus has three activation dates: June 6 (Robert Kennedy's
assassination in 1968), November 18 (death of Joseph Kennedy
in 1969), and November 22 (John F. Kennedy's assassination in
1963) of any year. On activation, the virus will display the
following message:
"Kennedy is deal - long live 'The Dead Kennedys'"
Two text strings can be found within the viral code:
"\command.com"
"The Dead Kennedys"
Infected systems will experience cross-linking of files, lost
clusters, and file allocation table errors.
Origin: Denmark April, 1990.
Stigmata: Stigmata is a 1,000 byte variant of the Tiny Virus.
It infects one .COM program in the current directory each
time an infected program is executed, though it will stop
infecting programs if it encounters a very small .COM file.
Programs infected with the Stigmata virus will have a file
length increase of 1,000 bytes with the virus being located at
the end of the file. The file's date and time in the DOS disk
directory listing will not be altered. No text strings are
visible within the viral code.
Origin: Unknown January, 1992.
Tiny-177: A 177 byte variant of the Tiny Virus, the Tiny-177
virus will infect one .COM file in the current directory each
time an infected program is executed. Infected programs will
have a file length increase of 177 bytes with the virus being
located at the end of the file. The file's date and time in
the DOS disk directory listing will be changed to the current
system date and time when infection occurred. One text string
is visible within the viral code:
"*.COM"
Origin: Unknown August, 1993.
Tiny-180: A 180 byte variant of the Tiny Virus, the Tiny-180
virus will infect one .COM file in the current directory each
time an infected program is executed. Infected programs will
have a file length increase of 180 bytes with the virus being
located at the end of the file. The file's date and time in
the DOS disk directory listing will not be altered. One text
string occurs in the viral code:
"*.COM"
The Tiny-180 virus does not infect very small files, and it
will usually not infect more than four files in the current
directory. It does nothing besides replicate.
Origin: Unknown June, 1993.
See: Tiny Family