Virus Name: Ada
V Status: Rare
Discovery: October, 1991
Symptoms: .COM file growth; slow clicking from system speaker;
decrease in available free memory
Eff Length: 2,600 Bytes
Type Code: PRsCK - Parasitic Resident .COM Infector
Detection Method: ViruScan, AVTK, Sweep, F-Prot, NAV, IBMAV,
NAVDX, VAlert, PCScan, ChAV,
NShld, LProt, Sweep/N, Innoc, NProt, AVTK/N,
Removal Instructions: Delete infected files
The Ada virus was discovered in Argentina in October, 1991. Ada
is a memory resident infector of .COM files, including COMMAND.COM.
The first time a program infected with the Ada virus is executed,
Ada will install itself memory resident as a low system memory TSR.
Available system memory as measured by the DOS CHKDSK program will
have decreased by 21,296 to 21,312 bytes. Interrupts 08, 13, and
21 will be hooked by the virus.
Once Ada is memory resident, it will infect .COM programs when they
are executed. If COMMAND.COM is executed, it will also become
infected. Programs infected with Ada will have a file size increase
of 2,600 bytes with the virus being located at the beginning of
infected files. There will be no visible change in the program's
date and time in the DOS disk directory. The following text strings
can be found in infected programs:
"HATI-HATI !! ADA VIRUS DISINI !!Delete"
Systems infected with Ada experience a slow clicking sound being
emitted from the system speaker. This clicking will occasionally
change in pitch. The user may also receive a "Disk full" error
even though the disk the user is attempting to write to is not