Ada Virus

Virus Name: Ada Aliases: V Status: Rare Discovery: October, 1991 Symptoms: .COM file growth; slow clicking from system speaker; decrease in available free memory Origin: Argentina 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, NAV/N, IBMAV/N Removal Instructions: Delete infected files General Comments: 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: "COMMAND.COM" "PCCILLIN.COM" "PCCILLIN.IMG" "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 actually full.