Rigor Virus
Virus Name: Rigor
Aliases: Rigor.373, Echo.B
V Status: Viron
Discovery: February, 1995
Symptoms: .EXE file corruption; file date/time changes;
message "Bad command or file name"
Origin: Unknown (possibly Australia)
Eff Length: 373 Bytes Overwriting
Type Code: ONE - Overwriting Non-Resident .EXE Infector
Detection Method: F-Prot, NAV, AVTK, Sweep, IBMAV, NAVDX, VAlert,
ViruScan, PCScan, ChAV,
Sweep/N, NProt, AVTK/N, NAV/N, IBMAV/N, NShld, Innoc 4.0+
Removal Instructions: Delete infected files
General Comments:
The Rigor, Rigor.373, or Echo.B, virus was received in February,
1995. Its origin or point of isolation is unknown. Rigor is a
non-resident, direct action overwriting virus which infects .EXE
files. It permanently corrupts the programs it infects.
When a program infected with the Rigor virus is executed, this virus
will infect the first uninfected .EXE file located in the current
directory by overwriting the first 373 bytes of the host program.
The virus will then display the following message and return the
system user to the DOS prompt:
"Bad command or file name"
Infected programs will not have any increase in size as the virus
overwrites the beginning 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 when infection occurred. The following
text strings are visible within the viral code in all infected
programs:
"*.EXE AUTOEXEC.BAT .."
"\MZREMECHO OFF"
"CLS"
"ECHO Greetings from RigorMortis and SCP/NuKe,Oz!"
"Bad command or file name"
Programs infected with the Rigor virus cannot be disinfected as a
portion of the host program has been overwritten. They should be
replaced with clean copies from a backup source.