Virus Name: AntiCMOS
V Status: Common
Isolated: April, 1995
Symptoms: BSC; Master boot sector (partition table sector) altered;
decrease in total system & available free memory;
System CMOS / Setup information erased
Eff Length: N/A
Type Code: BRhX - Resident Boot Sector & Master Boot Sector Infector
Detection Method: F-Prot, ViruScan, AVTK, IBMAV, NAV,
Sweep, NAVDX, VAlert, PCScan, ChAV
The AntiCMOS virus was received in April, 1995, though it has been
reported from sites in North America for several months. AntiCMOS
is a memory resident infector of diskette boot sectors as well as
the system hard disk master boot sector.
When the system is first booted from an AntiCMOS infected diskette,
this virus will infect the system hard disk master boot sector. It
does not become memory resident at this time. AntiCMOS becomes
memory resident when the system is booted from the system hard disk.
When the AntiCMOS virus is memory resident, total system and
available free memory, as indicated by the DOS CHKDSK program, will
have decreased by 2,048 bytes.
Once the AntiCMOS virus is memory resident, it will infect un-write
protected diskettes by infecting the diskette boot sector when they
are accessed, though it does not always infect the diskette.
The AntiCMOS virus contains code to erase the CMOS or system setup