Virus Name: Parity
V Status: Rare
Discovered: December, 1990
Symptoms: .COM file growth; long .COM program loads; possibly
intermittent parity errors
Eff Length: 441 Bytes
Type Code: PNCK - Parasitic Non-Resident .COM Infector
Detection Method: ViruScan, AVTK, F-Prot, NAV, Sweep, IBMAV,
NAVDX, VAlert, PCScan, ChAV,
NShld, LProt, Sweep/N, Innoc, NProt, AVTK/N,
Removal Instructions: Delete infected files
The Parity virus was received in December, 1990, and originated in
Bulgaria. This virus is a non-memory resident infector of .COM
files, and will infect COMMAND.COM.
When a program infected with the Parity virus is executed, the
virus will infect all .COM files in the current directory. If
COMMAND.COM is in the current directory, it will become infected.
Infected .COM programs will increase in length by 441 bytes, the
virus being located at the end of the infected program. The
program's date and time in the disk directory will not be altered
by the virus.
The major symptom of a Parity virus infection is that it will take
significantly longer to load and execute infected .COM files. The
increase in time is due to the virus searching the current drive
for .COM files to infect.
This virus may also display a message "PARITY CHECK 2" at times,
and halt the system.