Virus Name: Sybille
V Status: New
Discovered: January, 1995
Symptoms: .EXE file growth; decrease in available free memory
Eff Length: 853 - 867 Bytes
Type Code: PRhE - Parasitic Resident .EXE Infector
Detection Method: F-Prot, AVTK, IBMAV, ViruScan, Sweep, NAV, PCScan,
IBMAV/N, NShld, Sweep/N, NProt, NAV/N, AVTK/N, Innoc 4.0+
Removal Instructions: Delete infected files
The Sybille or Sybille.853 virus was received in January, 1995. Its
origin or point of isolation is unknown. Sybille is a memory
resident infector of .EXE files.
When the first Sybille infected program is executed, this virus will
install itself memory resident at the top of system memory but below
the 640K DOS boundary, not moving interrupt 12's return. Available
free memory, as indicated by the DOS CHKDSK program from DOS 5.0,
will have decreased by approximately 912 bytes. Interrupts 21 and
2F will be hooked by the virus in memory.
Once the Sybille virus is memory resident, it may infect .EXE files
when they are executed. Infected .EXE files will have a file length
increase of 853 to 867 bytes with the virus being located at the
end of the file. The file's date and time in the DOS disk directory
listing will not be altered. The following text strings are visible
within the viral code:
"@:\AUTOEXEC.BAT @echo off"
"echo Looking for Sibylle..."
It is unknown what the Sybille virus may do besides replicate.
Known variant(s) of Sybille are:
Sybille.1200: Received in May, 1995, Sybille.1200 is a 1,200
byte variant of the Sybille virus described above. Its size
in memory is 2,400 bytes, hooking interrupts 21 and 2F. It
may, but does not always, infect .EXE files when they are
executed. Infected files will have a file length increase of
1,200 to 1,214 bytes with the virus being located at the end
of the file. The program's date and time in the DOS disk
directory listing will not be altered. The following text
strings are encrypted within the viral code:
"FUCKING CRACKER - DIE !!!"
"(P) 1992 BY AZTECH.INC"
Origin: Unknown May, 1995.